LEWISTON, Maine (AP) — Lawyers for 100 survivors and relatives of victims of the deadliest shooting in Maine history have begun the formal process of suing the U.S. Army and an Army hospital for what they say was a failure to act to stop the reservist responsible for the crime, attorneys announced Tuesday.

The individual notices of claim say the Army was aware of the reservist's mental health decline that left him paranoid, delusional and expressing homicidal ideations, producing a "hit list" of those he wanted to attack.

“It is difficult to conceive of a case in which Army personnel could have more warning signs and opportunities to intervene to prevent a service member from committing a mass shooting than what happened in the case of Army Reservist Robert Card,” lawyers wrote in their notices mailed Friday.

The notices of claim by four law firms are a required step in suing the federal government. The Army will have six months to determine whether to respond, after which a lawsuit may be filed. The Army had no immediate response Tuesday.

Eighteen people were killed when the 40-year-old Card opened fire at two locations he'd frequented — a bowling alley and a cornhole league hosted by a bar and grill — on Oct. 25, 2023. An additional 13 people were injured. Card was found dead by suicide two days later.

An independent commission appointed by Maine's governor concluded that there were ample opportunities to intervene by both civilian law enforcement and the Army. For now, lawyers for victims, as well as relatives and friends who suffered loss, are focusing on the Army, not on a private hospital that treated Card or on civilian law enforcement.

The Department of Defense, U.S. Army and Army Keller Hospital “broke its promises, failed to act reasonably, violated its own polices and procedures and disregarded directives and orders,” the claim said.

In September 2023, when Card threatened to “shoot up” an armory and his friend warned of "a mass shooting,” the Army did not provide critical background about two doctors recommending that Card not have access to weapons when it requested that local law enforcement officers check on his well-being, the claims said. Card's commanding officer even downplayed the threat by undercutting the credibility of the soldier who issued the warning and by declining to share all information at his disposal, the claims said.

Cynthia Young, whose husband, William, and 14-year-old son, Aaron, were killed at the bowling alley, said in a statement that the pain and trauma never go away. “As terrible as the shooting was, it’s even more tragic that there were many opportunities to prevent this and they were not taken,” she added.

The filings said there may have been a time when mass shootings were so rare that they couldn’t be predicted, but “that has not been true in America for decades.”

“Mass shootings, like what happened in Lewiston, are an epidemic in America. Consequently, those in positions of responsibility and authority are required to appreciate the warning signs and behaviors that telegraph the risk of mass violence, take them seriously, and act to prevent their occurrence," the claims said.

FILE — In this image taken from New York State Police body camera video that was obtained by WMTW-TV 8 in Portland, Maine, New York State Police interview Army reservist Robert Card, the man responsible for Maine's deadliest mass shooting, at Camp Smith, in Cortlandt, N.Y., July 16, 2023. (WMTW-TV 8/New York State Police via AP, File)

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FILE - Law enforcement personnel are staged in a school parking lot during a manhunt for Robert Card in the aftermath of a mass shooting in Lewiston, Maine, Oct. 27, 2023. (AP Photo/Matt Rourke, File)

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FILE - Rain-soaked memorials for those who died in a mass shooting sit along the roadside by Schemengees Bar & Grille, Oct. 30, 2023, in Lewiston, Maine. (AP Photo/Matt York, File)

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FILE - A woman visits a makeshift memorial outside Sparetime Bowling Alley, the site of a mass shooting, Oct. 28, 2023, in Lewiston, Maine. (AP Photo/Robert F. Bukaty, File)

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FILE - A man photographs a make-shift memorial at the base of the Lewiston sign at Veteran's Memorial Park, Oct. 29, 2023, in Lewiston, Maine. (AP Photo/Matt York, File)

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