Hundreds look for Maine mass shooting suspect

More than 74,000 residents in Lewiston, Maine, and surrounding areas remained in a lockdown Thursday with schools and business closed as law enforcement authorities searched on the ground, in the air and on water for a man suspected of killing 18 people and wounding 13 others Wednesday night at a bowling alley and a local bar in Lewiston, officials said.

Police have issued a warrant for the arrest of Robert Card, 40, for eight counts of murder — one for each victim identified so far. The shooting is the deadliest one in the United States this year and the eighth-deadliest attack since 2006.

More than 350 police officers are involved in the search, authorities said. US Senator Susan Collins of Maine said on Thursday that at least 80 FBI agents are looking for Card, along with the US Coast Guard and agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF).

A Coast Guard official told CBS News that it has deployed resources to search the Kennebec River for the suspect after a vehicle was found near a boat launch.

Card's family is cooperating with authorities, ABC News and CNN reported. Card's sister told investigators she thought that Card might have been looking for an ex-girlfriend at the shooting locations.

Ryan Card, the suspect's brother, told CNN via text, "There are many people hurting out there; please focus on them. This is many people's worst nightmare.'"

Maine officials haven't addressed a potential motive for the shootings but said during a media briefing Thursday that they are looking into Card's mental health.

Card allegedly threatened other soldiers with violence and was "command directed" to go to the Keller Army Community Hospital at the US Military Academy at West Point, New York, for medical evaluation, the official said. New York State Police transported Card to the hospital for a medical evaluation, the official said.

A police bulletin sent to law enforcement said Card had been in a mental health facility for two weeks in the summer and that he had reported "hearing voices and threats to shoot up" the military base.

No information was provided about Card's treatment or diagnosis. He received roughly two weeks of inpatient psychiatric treatment after making concerning comments, according to a person familiar with investigators' findings, The Associated Press reported.

In other developments, authorities found the suspect's white Subaru at a location in Lisbon, several miles southeast of Lewiston, late Wednesday, and recovered a firearm from the vehicle, several law enforcement sources told ABC News.

Authorities are testing and tracing the gun to determine if it was involved in the shooting, according to the sources. The weapon used in the shootings was a semiautomatic rifle with an extended magazine and scope, CBS News reported.

Investigators found a note at Card's home on Thursday, law enforcement sources familiar with the case told ABC News, though they declined to describe its contents, length or relevance to the investigation.

The shooting unfolded in part during a youth night at a local bowling alley. Witnesses described a desperate scene where people hid behind benches and tables and even inside the bowling pin machine at the end of a lane.

Meghan Hutchinson was at the bowling alley with her 10-year-old daughter Zoey Levesque, who was grazed by a bullet.

"I never thought I'd grow up and get a bullet in my leg," she said. "Like, why do people do this? I was more worried about, like, am I going to live and going to make it out of here? Like, what's going to happen? Are the cops going to come?"

Leroy Walker told NBC Nightly News that his son Joseph had used a butcher's knife to try to fight Card. Joseph was the manager at Schemengees Bar and Grille, the second place that police said Card opened fire at on Wednesday evening.

Walker said state police told him that his son "tried to go at the gunman to stop him from shooting anybody else. The gunman shot him twice through the stomach."

Walker, a City Council member in Auburn, Maine, also told MSNBC that it took nearly 14 hours to get an update about his son, and he and his family are now "suffering and dying in a nightmare we don't understand".

Among those who were wounded was Jessica Karcher's 23-year-old son. She told The Washington Post that he was hit at the bar and grille, the other location where the gunman opened fire.

She said he was hit four times, underwent emergency surgery and remains in critical condition. Doctors have to "keep resuscitating him", she said. "He's not out of the woods."

Chad Vincent told The New York Times that he was in the fifth frame of his weekly bowling league game at Just-In-Time Recreation on Wednesday night when he heard a loud sound. But then, perhaps five seconds later, came another bang: "One of my bowling partners said, 'Hey, that's a gun! That's gunshots!'"

Vincent, 45, ran toward the back exit. As he was escaping, he called 911. He and most of the other members of the league made it out of the building and through the woods to an Italian restaurant, Vincent said. They locked themselves in for maybe five to 10 minutes before their loved ones started arriving to pick them up.

As he and others fled, he said they were in disbelief.

"We're going: 'This is Maine,'" he said. "This is not happening. This stuff doesn't happen in Maine. Everybody's nice. We usually don't have problems."

Agencies contributed to this story.