Police were told Maine gunman might 'snap and commit a mass shooting' 6 weeks before massacre

Editor's note: This story has been updated to state that the U.S. Army sent a letter to the Sagadahoc County Sheriff's Office regarding Card. An original report incorrectly stated the national guard sent the letter.

Law enforcement officials in Maine had previously been made aware that the perpetrator of the recent mass shooting in Lewiston, Maine last week that killed 18 and wounded 13 was on the verge of a violent outburst, according to a new report.

CNN reported Monday that in September, the US Army sent a letter to the Sagadahoc County Sheriff's Office warning that 40-year-old Army reservist Robert Card could potentially "snap and commit a mass shooting," according to an unnamed service member concerned about Card. County sheriffs tried unsuccessfully to conduct a welfare check at Card's home on September 16, though Card apparently refused to answer the door or talk to the responding officer.

According to CNN's unnamed source, the Sagadahoc County sheriff's deputy who responded generated a File 6 missing person's report on card, but the case appeared to have been closed on October 1 — roughly three weeks before Card went on two separate shooting sprees at a bowling alley and a local bar and restaurant.

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The letter in question detailed how Card was kept at a mental health facility for a 14-day period in July, following an altercation with several fellow service members. While at West Point this summer, Card and several others were on their way to a convenience store to buy beer, when Card accused one of his fellow reservists of calling Card a pedophile.

"One of the soldiers who had been friends with [him] for a long time was there. [He] got in his face, shoved him, and told him to stop calling him a pedophile," the letter read.

The day after the altercation, one of the men present with Card took him to a base hospital, where staff deemed Card in need of further treatment, leading to the 14-day stay. After Card's release, he reportedly had another altercation with another member of the Maine National Guard while they were on their way back from a casino. When Card started making threats in regard to people calling him a pedophile, a friend tried to calm him down, only for Card to allegedly punch him in the face.

"When [his friend] told him to knock it off because he was going to get into trouble talking about shooting up places and people, [he] punched him,” the statement said. “According to [the friend], [he] said he has guns and is going to shoot up the drill center at Saco and other places … [the friend] is concerned that [he] is going to snap and commit a mass shooting," the letter read.

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After the shooting last Wednesday, Card fled in his vehicle, triggering a manhunt involving several law enforcement agencies. Card was found dead of an apparent self-inflicted gunshot wound several days after the shooting.