Lewiston, Maine became the scene of America's latest mass killing Wednesday night when a man opened fire inside a bar and a bowling alley, killing at least 18 people and wounding dozens more.

In the aftermath of the deadly attack, hundreds of law enforcement agents descended on the area and urged residents to find safety as a massive manhunt unfolds for a person of interest, a trained firearms instructor identified as 40-year-old Robert Card.

The shooting became the deadliest mass killing this year in the United States, but it was far from the first. Before the rampage in Maine, 35 mass killings had already unfolded across the nation so far in 2023, according to a database maintained by USA Today and The Associated Press in partnership with Northeastern University. The database includes every mass killing since 2006 from all weapons in which four or more people, excluding the offender, were killed within a 24-hour time frame. The database also includes dozens of variables on each incident, offender, victim, and weapon.

Hours after the carnage in Maine, another mass killing unfolded Thursday morning in Clinton, North Carolina, where five people with an ages range from 30s to 80s were found fatally shot in a home.

So far, this year's violence has claimed the lives of 195 people, though the death toll could change if the number of victims in Lewiston continues to rise Thursday.

With more than two months left in the year, the nation has witnessed the third-most mass-killing events in a single year since 2006, the year the database was launched.

Last year, 210 people were killed in 42 mass killings. The highest death toll came in 2019, when 234 deaths were reported in 46 mass killings.

Here's what happened in the other mass killings this year.

Live updates:Police search for 'armed and dangerous' man after Maine shooting

Romeoville, Illinois: Sept. 17

A family of two adults and two children were found dead with gunshots wounds at their home in Romeoville, Illinois, a small village approximately 30 miles southwest of Chicago when police were called on a wellness check. A 31-year-old man and an unidentified woman suspected in their deaths were later found dead with gunshot wounds following a police chase.

Mass killing database:Revealing trends, details and anguish of every US event since 2006

Lake Township, Ohio: Aug. 24

Police performing a welfare check found five people, including three children, dead in an apparent quadruple murder-suicide. Authorities investigated the killings as a domestic dispute that turned deadly.

Oklahoma City: Aug. 16

Police responding to a reported domestic disturbance found a family of five, including three children, all shot to death. Investigators later determined that a 28-year-old man likely killed his family before taking his own life.

Hampton, Georgia: July 15

A 40-year-old man wanted in a series of shootings in an Atlanta suburb that left four people dead was shot and killed by police. The victims, three men and one woman, were all in the 60s, police said.

What to know about Lewiston:Town in Maine became the scene of America's latest mass shooting that left at least 16 people dead

Shreveport, Louisiana: July 4

Four people were killed and seven wounded in a shooting at a Fourth of July block party after several males exchanged gunfire. Suspects were not quickly identified, and arrests were not immediately made.

Philadelphia: July 3

A 40-year-old Philadelphia man wearing a bulletproof vest and armed with an assault rifle and a handgun was charged with killing five people. Police said the suspect was shooting at people "seemingly at random" on neighborhood streets before he was cornered in an alley and surrendered.

Green Pond, South Carolina: July 2

What began as a report of a house fire turned into a massive murder investigation when authorities discovered six people had died and one suffered critical injuries at the community of Greenpond, near Walterboro, about 40 miles from Charleston. A 33-year-old man was eventually charged with murder in the killings of his sister-in-law and 11-year-old daughter, the Associated Press reported.

Kellogg, Idaho: June 18

A 31-year-old man was arrested after authorities said he shot and killed four of his neighbors inside their home. Authorities didn't specify an exact motive for the attack, but police said the slayings came on the heels of a dispute between the victims and the suspect's family.

Sequatchie, Tennessee: June 15

A murder-suicide in an unincorporated town west of Chattanooga left six people dead and one injured. A 48-year-old man was thought to be responsible for killing himself and the others — including three children and his estranged wife — in a home police found ablaze, according to the Associated Press.

Mesa, Arizona: May 26

A 20-year-old suspect was arrested in connection to five separate shootings in the Phoenix metro area that left four people dead and one person injured. The 12-hour crime spree included four separate shootings in Mesa, Arizona, and one in Phoenix, police said. 

Nash, Texas: May 23

Officers responding to a report that an armed male was barricaded inside a home eventually arrested an 18-year-old after a standoff. The teen was charged with murder after police said he killed his parents, sister and brother, the Associated Press reported.

Allen, Texas: May 6

A 33-year-old man opened fire at a busy shopping mall, killing eight people and wounding 10 more before police fatally shot him. Social media posts attributed to the shooter revealed his interest in far-right extremism, white supremacy, Nazism and anti-Semitism.

Lake Wales, Florida: May 2

A 38-year-old man was suspected of fatally shooting a woman and her three children after police were called to an apartment complex where they found the bodies. After an hourslong standoff at a motel, police fatally shot the man, according to the Associated Press.

Henryetta, Oklahoma: May 1

A 39-year-old convicted rapist was among the seven people found dead at his property in rural Oklahoma. Police determined that shot his wife, her three children and their two friends before killing himself days before he was due in court for a different sex offense.

Mojave, California: April 30

Four people were found fatally shot inside an RV in a remote Mojave Desert community, authorities said. There were no immediate arrests, but two people were being sought for questioning as “persons of interest,” the Associated Press reported.

Cleveland, Texas: April 28

A manhunt ensued after a 38-year-old male suspect in a shooting rampage at a rural Texas home killed five people 45 miles north of Houston. The deadly attack spurred anger over the suspect's immigration status after it was revealed that he had been deported four times since 2009.

Bowdoin, Maine: April 18

A Maine man fatally shot his parents and a couple in their Portland-area home before firing at passing cars on an interstate where he hit three members of another family, critically injuring one. , The 34-year-old then fled onto nearby I-295, where he began firing at passing cars, believing he was being chased by police. Authorities arrested him after he ditched his vehicles, hours after police discovered the bodies in the small town.

Who is Robert Card?Man wanted for questioning in Maine mass shooting

Dadeville, Alabama: April 15

Four people were killed and 28 were injured in a shooting during a teenager’s birthday party. Police did not have initial confirmation about what led to the shooting and did not identify a suspect, although they said the person was no longer a threat to the community.

Louisville, Kentucky: April 10

A 25-year-old man shot and killed five people and injured 8 others, including a police officer, where he worked. Police arrived as shot were still being fired at Old National Bank in Louisville and shot and killed the gunman. The man, whose parents said his brain would be tested for CTE, left a note behind saying he was suicidal.

Monroe, Louisiana: March 31

A 37-year-old man was arrested on arson and murder charges after a fire killed four people in a home, KNOE-TV reported.

Nashville, Tennessee: March 27

A 28-year-old man fatally shot three adults and three children at The Covenant School, a private Christian school in Nashville before police killed him. The gunman was a former student at the school.

Sumter, South Carolina: March 21

A 42-year-old former soldier shot and killed three children as they slept in their home while their mother, his ex-wife, frantically sought help, the Associated Press reported. He also killed an Army soldier who was at the home before killing himself.

Birmingham, Alabama: March 13 to 14

A 28-year-old man was suspected of killing four people in overnight shootings, according to the Associated Press. Authorities said the man approached a police officer and said he had shot two people in Birmingham and two people in St. Clair County.

Dallas, Texas: March 12

An 18-year-old man and 20-year-old woman were charged in the fatal shootings of four people at an apartment after telling police they’d broken into the home to take money, the Associated Press reported. The man admitted to shooting all of the victims, while woman had dated one of the victims with whom she was involved in a custody dispute over their son.

Miami Lakes, Florida: March 10

Police found three females and two males dead from gunshot wounds inside a home, the Associated Press reported. The wounds of one man appeared to be self-inflicted, leading investigators to believe the case was a murder-suicide.

Cocoa, Florida: March 1

A 36-year-old man was arrested after fatally shooting his teenage daughter, her mother and two other people, the Associated Press reported. Deputies responded after one of two surviving children had called a relative for help.

Daphne, Alabama: Feb. 22

A 21-year-old man was accused of killing his grandparents, his brother and a family friend with a handgun and pickaxe, according to the Associated Press. Police found their bodies on his grandparents property in both the backyard and inside a bedroom in the house.

Arkabutla, Mississippi: Feb. 17

A lone gunman identified as a 52-year-old man killed six people, including his ex-wife, in a series of shootings in a rural Mississippi town. The man was armed with a shotgun and two handguns.

Luttrell, Tennessee: Jan. 29

A 52-year-old man who complained of having “a devil in his head” fatally shot four children in his home before setting the residence ablaze and shooting himself, the Associated Press reported. The children, ages 5 to 15, had been shot multiple times.

Half Moon Bay, California: Jan 23

Seven people were killed in two related shootings in the coastal community south of San Francisco. The shootings happened at two plant nurseries on the outskirts of Half Moon Bay, and a 66-year-old who worked there was eventually charged and pleaded not guilty.

Monterey Park, California: Jan. 21

A 72-year-old gunman killed 11 people and injured nine at a Lunar New Year Festival in Monterey Park. The man took his own life while sitting in his van as law enforcement agents approached.

Goshen, California: Jan. 16

A family of six were killed "cartel-style execution" in a home in the small community of Goshen, including a young mother and her 10-month-old baby. A 35-year-old man and a 25-year man were later arrested and pleaded not guilty in the killings, which police believe were gang-related.

Cleveland, Ohio: Jan. 13

A 41-year-old man was accused of fatally shooting his father, sister and nephew as well as another man and critically wounding an 8-year-old girl, the Associated Press reported. Police believe he shot the victims in the head in different rooms of a home before he flagged down a police cruiser and directed officers to the scene.

High Point, North Carolina: Jan. 7

A 45-year-old man shot and killed his wife and three children before turning the gun on himself, the Associated Press reported. Two others escaped the house, one of whom was a relative of the family.

Enoch, Utah: Jan. 4

A 42-year-old Utah man fatally shot his wife, five children, mother-in-law and then himself after his wife filed for divorce.

Contributing: The Associated Press

Eric Lagatta covers breaking and trending news for USA TODAY. Reach him at elagatta@gannett.com

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