(LEWISTON, Maine) — At least 20 people are believed to be dead and dozens more have been injured after a bowling alley came under fire in Lewiston, Maine, Wednesday evening, law enforcement sources confirmed to ABC News.

A nurse at Maine Medical Center told ABC News the shooting unfolded at a bowling alley during its youth night.

“Maine Medical is on lockdown right now awaiting Lewiston patients,” the nurse said. “They just called for [emergency department] nurses and critical care nurses to come in, set up three stretchers to each single critical care bay. They just got their first two patients — both gunshot wounds to their thighs.”

Lewiston police have identified a person of interest as Robert Card, who’s still at large.

Card allegedly has a history of military service and is a firearms instructor, sources said.

The sources said he also has a mental health history, including a two-week stay this summer at a mental health facility after he allegedly made threats about carrying out a shooting at a National Guard facility.

Authorities have traced his white Subaru to a location in Lisbon, Maine, sources said, as the manhunt continues.

“We were inside. Just a normal night of bowling and out of nowhere he just came in and there was a loud pop,” an eyewitness to the shooting named Brandon, whose last name was not made available, told ABC News. “Thought it was a balloon. I had my back turned to the door. As soon as I turned and saw that it was not a balloon, he was holding a weapon. I just bucked it down the lane and I slid basically into where the pins are and climbed up to the machine and was on top of the machines for about 10 minutes until the cops got there.”

Meghan Hutchinson, another shooting witness, said “We were very scared and we didn’t know, like, we didn’t know what to do, what to expect from this. You know, nothing like this has ever happened here before. We barricaded in there and another parent was in the room with me. She had a phone and she called 911.”

“I never thought I’d grow up and get a bullet in my leg,” said Zoey Levesque, who was Injured in the Wednesday night shooting. “Like, why do people do this? I was more worried about, like, am I going to live and I going to make it out of here. Like, what’s going to happen? Are the cops going to come?”

Elsewhere, the White House said Wednesday evening, “The President has been briefed on what’s known so far about the mass shooting in Lewiston, Maine and will continue to receive updates.”

Gov. Janet Mills posted on X that she was aware of the situation and urging “all people in the area to follow the direction of State and local enforcement. I will continue to monitor the situation and remain in close contact with public safety officials.”

According to the Gun Violence Archive, the mass shooting in Lewiston, Maine, is already the deadliest shooting of the year.

Meanwhile, municipal offices in Lewiston and Lisbon, Maine, will be closed on Thursday, officials said. In Lewiston, where the mass shooting occurred, officials said they would also close the library and cancel all events, including early voting, at city buildings.

“Non-emergency personnel should stay at home tomorrow too,” the city said in a social media post.

Maine State Police plan on briefing the media at 10:30 a.m. ET on the mass shooting in Lewiston.

“I am heartbroken for our city and our people,” Lewiston Mayor Carl Sheline said in a statement. “Lewiston is known for our strength and grit and we will need both in the days to come.”

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