A U.S. Army investigation into the reservist who fatally shot 18 people last year in Maine's deadliest mass killing found several lapses in his unit's handling of warning signs leading up to the massacre, according to findings released Tuesday.

Three officers in the gunman's chain of command have been disciplined for dereliction of duty, the Army said in its report, citing failures after several alarm bells rang about Robert Card's intent to commit violence. The report said unit leadership made several attempts to address Card's mental health but there were also a "series of failures," citing communication gaps and procedural missteps.

Army officials said the officers were disciplined with "adverse administrative action" that can prevent military advancement, the Army said in its report. They did not provide further specifics. Each was found in "dereliction of duty," according to the report.

The report said unit leadership made several attempts to address Card's mental health but there were also a "series of failures," including communication gaps and procedural missteps.

The disciplined officers were not identified since they are all in the rank of colonel or below, the report said, citing Army policy.

Family members, friends and coworkers had been raising concerns about the 40-year-old reservist's deteriorating mental health and threats for months, the Army's report said, and law enforcement knew he had a stash of firearms in his home but failed to confiscate them.

On Oct. 25, Card opened fire at a bar and a bowling alley in Lewiston, Maine. Two days later, after an intense search that kept residents locked in their homes, authorities found him dead of a self-inflicted gunshot wound.

“It is Army leadership’s sincere hope that these medical reviews and expert analysis, improved procedures and policies, updated training and information sessions, and adverse administrative action against those who were derelict in their duties, will help us determine how these events happened, and help prevent similar tragedies in the future," the report said.

Red flags before shooting rampage

Friends, family members and coworkers first noticed a decline in Card’s mental health in January 2023, the Army report said. Witnesses testified that he began to hear voices and believed his loved ones had turned against him.

By May 2023, Card’s family has reported at least four “alarming mental health incidents” to local law enforcement, and officers were also aware he had 10 to 15 firearms at his home. Local law enforcement told Card’s chain of command about his decline. But when Card showed up for mandatory Army Reserve Battle Assembly the next month, no one discussed his mental health challenges with him. Unit members said he seemed normal, according to the report.

In July 2023, Card attended his annual training, but was ordered to undergo a behavioral health evaluation at Keller Army Community Hospital in West Point, New York, within hours of his arrival because of signs of a “deteriorating mental state.” After an initial screening, the hospital transported him to Four Winds Hospital for additional care.

Card was placed on a 90-day behavioral health profile, which restricted his access to military-issued weapons. Medical professionals also recommended restricting access to his personally owned firearms. The report said Card's chain of command tried to "coordinate the removal of Card’s weapons from his home, but they lacked the authority to legally compel the removal of any firearms or weapons.”

The reservist was hospitalized at Four Winds for 19 days and diagnosed with Brief Psychotic Disorder. In his discharge summary, which was provided to the military hospital, medical professionals said Card had "homicidal ideations."

In August and September 2023, Card "communicated increasingly violent, yet vague, threats and rhetoric" to friends and family members, the report said. He often talked about how many people he could hurt and what locations he could "shoot up."

Card’s friend, who was in his reserve unit, also contacted the unit chain of command after Card violently attacked him, and said he was concerned his friend was "going to snap and commit a mass shooting." Army officials relayed the concerns to local law enforcement, and the Army Reserve Medical Management Center also tried to reach Card about his treatment. After failing to contact him, they extended his behavioral health profile for another 90 days on Oct. 17.

Days later, Card committed the worst mass shooting in Maine history.

Other investigations

Tuesday’s report noted that the Army’s findings were provided to the Department of Forensic Psychology at Walter Reed for medical review and analysis. The Maine State Police and an independent state commission are also conducting separate investigations into the shooting.

Maine Gov. Janet Mills established an independent commission in November to investigate the shooting. The group released an initial report in March, which concluded that the Sagadahoc County Sheriff’s Office had “sufficient probable cause” to take Card into protective custody and take his firearms in September 2023 under Maine’s red flag law.