A statewide awareness alert was issued last month to all Maine law enforcement agencies after a U.S. Army reservist made threats against his base, highlighting another red flag authorities missed before 18 people were fatally shot last week.

Robert Card, 40, was found dead late Friday, ending a massive manhunt that sent residents across several Maine communities in panic and under shelter-in-place orders. Card's body was discovered at a recycling center in Lisbon Falls, Maine, and officials said he died of an apparent self-inflicted gunshot wound.

Lisbon Falls is about 11 miles southeast of Lewiston, Maine, where Card was suspected of killing 18 people and injuring 13 others at a bowling alley and a bar on Wednesday. The shooting rampage followed recent reports of Card's mental illness and "veiled threats" made to his military base, according to authorities.

Two local law enforcement chiefs told The Associated Press that an alert was sent in mid-September to watch for Card who made threats against his base and fellow soldiers in Saco, Maine. But after futile attempts to search for Card, law enforcement agencies moved on.

"We added extra patrols, we did that for about two weeks. ... The guy never showed up," Saco Police Chief Jack Clements told The Associated Press.

The reservist's alleged threats and mental health struggles have raised concerns over Maine's gun safety laws and what could have been done to prevent the shooting.

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'We couldn't locate him'

Sagadahoc County Sheriff Joel Merry, whose jurisdiction includes Card's home in Bowdoin, said the awareness alert was sent to every law enforcement agency in the state after his deputy conducted a welfare check of Card's home and was unable to find Card.

"We couldn't locate him," Merry told the Associated Press, adding that he couldn't recall if there was any follow-up because "I don't have any reports in front of me."

Clements defended his department's to the alert about Card, describing it as a "generic thing that came out saying, hey, you know, we've had some report that this guy's made some veiled threats." He added that such alerts are common and his department had given the alert about Card its due attention.

"Never came in contact with this guy, never received any phone calls from the reserve center saying, 'Hey, we got somebody who was causing a problem,'" Clements said. "We never got anything."

Card taken by authorities for evaluation mid-July

In mid-July, Card was taken by police for an evaluation after military officials became concerned about his erratic behavior, The Associated Press reported.

New York State Police troopers were called in on July 16 to West Point by commanders of the Army Reserve's 3rd Battalion, 304th Infantry Regiment, according to a New York State Police document reviewed by The Associated Press. The document said Card had made "threats to other members of his military unit" during a training exercise.

Police had said Card was "hearing voices and threats to shoot up" a military base. State Police troopers took Card to the Keller Army Community Hospital at West Point for a two-week mental health evaluation.

But Maine Department of Public Safety Commissioner Michael Sauschuck said in a news conference Saturday that despite Card's history of mental illness, there was no record of him being involuntarily committed to a mental health facility.

"Just because there appears to be a mental health nexus to this scenario, the vast majority of people with mental health diagnosis will never hurt anybody," Sauschuck said.

Several firearms were recovered in the search and investigation of Card. The guns recovered were legally purchased, officials said.

On Wednesday, police had found a rifle in Card's abandoned car. And on Friday, two firearms were discovered with Card's body in a trailer on the Maine Recycling Corp. property, where Card once worked.

Card was not on the state’s "yellow flag” list that only allows law enforcement to limit gun ownership, a spokeswoman for the Maine Attorney General’s Office confirmed to USA TODAY. Maine's "yellow flag" law is an alternative to "red flag" laws around the United States, which allow law enforcement and judges to remove an individual's access to firearms.

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Residents gather to pray, reflect on deadly massacre

Maine residents gathered at churches on Sunday to pray and offer each other support in light of the shooting.

At the Basilica of Saints Peter and Paul in Lewiston, the Rev. Daniel Greenleaf started the service with a moment of silence. Greenleaf told the congregation that it was good to be able to pray together after days of sheltering in place.

“We can see the rays of light in darkness,“ Greenleaf said during his sermon. “We cannot fix this, but then again human beings are not machines to be fixed."

During a service at Lisbon Falls Baptist Church, the Rev. Brian Ganong prayed for the community. “It did happen. We may never know the reason why,” he said during the service.

Some residents had gathered at a makeshift memorial to the victims down the street from the bar targeted by Card. Other residents tried to return to normalcy and went about their days.

Leroy Walker, an Auburn city councilor and father of one of the victims, greeted and hugged people at a trick-or-treat event on Sunday that was hosted by an organization he leads. But when remembering his son, Joseph, who would've joined him at the event, Walker became emotional.

“It’s been a tough few days, trust me. The heart doesn’t stop bleeding,” Walker told The Associated Press. “I miss him every minute. I miss him more every day.”

Contributing: Eduardo Cuevas and Terry Collins, USA TODAY; The Associated Press