At least eleven people were killed and scores more injured in multiple shootings across the country over the weekend, according to officials, as the nation grapples with the mounting toll of gun violence.

Since Friday, 12 mass shootings – defined as when four or more people, not including the shooter, are shot or killed – have occurred across the nation, according to the Gun Violence Archive. Many of the shootings, including those in Chicago and Indianapolis, happened at large Halloween gatherings in the early hours of Sunday. 

The Halloween weekend shootings come just days after a gunman opened fire at a bowling alley and restaurant in Maine, killing 18 people and injuring 13 others, in the deadliest shooting so far this year. The massacre sparked outrage across the country, with politicians calling for stricter gun control laws.

Here's what we know about the weekend's shootings:

3 killed in Texarkana, Texas Halloween party

In Texarkana, Texas, three people were killed in a shooting at a party in the back room of a business Saturday night just after 9 p.m., police said in a statement. One man died at the scene, and another man and a woman died overnight at a hospital, officials said. 

“Apparently, this all started when a fistfight broke out between two men at the party. At some point during this fight, at least two men there pulled out rifles and started shooting,” Texarkana Texas Police said in a statement. 

In total, six people, ages ranging from 19 to 31, were shot at the party. Two men and a woman are recovering at a hospital with non-life-threatening injuries, police said.

Police identified Breoskii Warren, 20, as a suspect in the shootings and are asking anyone with more information to come forward.

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2 killed, 15 shot in Tampa, Florida

Two people were killed and 15 were injured in a shooting Sunday just before 3 a.m. at a Halloween party in the Tampa, Florida, neighborhood of Ybor City, police said.

A Tampa Police Department release described the incident as "an altercation between two groups [that] escalated to gunfire." A 14-year-old boy and a 22-year-old man were killed in the shooting, officials said.

One person was dead at the scene and another died after being transported to a hospital, according to police. Fifteen people were shot, one with serious injuries, officials said in a Sunday afternoon news conference.

Police were present at the scene just as bars were closing and people were pouring into the streets and responded within seconds, according to CNN.

Tyrell Stephen Phillips, 22, was arrested and charged with second-degree murder with a firearm, police said. Officials recovered two firearms at the scene, one of which was stolen.

1 killed, 9 injured at industrial park party in Indianapolis

In Indianapolis, 10 people aged 16 to 22 were shot, one of them fatally, at a party in an industrial park early Sunday, the Indianapolis Star, part of the USA TODAY Network, reported.

Indianapolis Metropolitan Police officers responded to a call about a large gathering at the park at midnight on Oct. 29. When they arrived, officers said they heard gunshots and saw a large crowd dispersing from the area, according to a statement.

A woman was pronounced dead at the scene. Nine others were injured, police said, but all of them are currently in stable condition.

Multiple firearms were reportedly found at the scene by investigators. The statement said officers had detained "numerous individuals" but no arrests have been made.

15 shot, two in critical condition, after Chicago party shooting

In Chicago, at least 15 people were shot, two critically, at a Halloween party on Sunday, police said in a statement. The victims include six women and nine men with ages ranging between 26 and 53, according to the release. 

Officers responding to reports of shots fired just after 1 a.m. in the North Lawndale neighborhood saw an unidentified man shooting into a large gathering, the Chicago Police Department said.

Police pursued the man on foot, and he was placed in custody shortly after, officials said.

A 26-year-old woman who was shot in the left hip and right buttocks and a 48-year-old man with three gunshot wounds to his hips and thighs were in critical condition, police said.

Calls for gun control in aftermath of mass shootings

Since Jan. 1, there have been at least 580 mass shootings in the country, according to the Gun Violence Archive. The weekend killings come as the nation mourns the victims of the deadly attacks in Lewiston, Maine, that sent residents across several communities in panic and under shelter-in-place orders.

Lawmakers have expressed their condolences to the families of the victims and to those injured in the Maine shootings. But some are urging their lawmakers to go further, saying Congress must work together to pass stricter gun control legislation like background checks, an assault weapons ban, and red flag laws that prevent certain individuals who pose a threat from purchasing a firearm.

Rep. Jared Golden, whose constituents died in the Maine massacre, has apologized for opposing gun reform action and called on Congress to enact an assault rifle ban. The conservative Democrat said he had opposed a ban on the "false confidence" that his community was above such violence.

"The time has now come for me to take responsibility for this failure, which is why I now call on the United States Congress to ban assault rifles like the one used by this sick perpetrator of this mass killing in my hometown of Lewiston, Maine," he said. 

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