NEW GLOUCESTER — Police are investigating a local man said to be keeping a “kill list” of the names of several public officials with whom he has differences.

Investigators at the Cumberland County Sheriff’s Department describe the matter as an old situation that has recently flared again. No charges had been filed as of Tuesday evening.

According to a source, the local man is Frank Staton Jr., 41. He recently made threats of violence via email and phone calls, town officials said. The issue was addressed last week by Board of Selectmen Chairman Steven Libby near the end of the board’s meeting. According to Libby, he received a menacing email, and Town Manager Paul First was threatened in a phone call from the same man.

“We both received criminal threats,” Libby said May 19. “The language in the email is very, very vulgar. This should not go unchecked.”

The threats had been reported to the Sheriff’s Department and an investigation was underway. According to Libby and others, the same man had been threatening violence against town officials dating back several years.

“This is not the first time this individual has made threats,” Libby said.

Town Manager First, at the same meeting, said it did not appear that political matters were behind the threats, although he did not specify what may have motivated them. At the meeting, he advised everyone in the room to be extra vigilant in coming days.

“What he’s clearly stated he’s doing is threatening the lives of any town officials,” First said. “Everyone needs to be on guard.”

First on Tuesday declined to turn over the threatening email, saying he considered it evidence in a criminal investigation.

Sheriff’s officials said Staton believes First and Libby conspired to steal signs from his front lawn, an accusation town officials have denied.

Cumberland County Sgt. Jim Estabrook was investigating the matter. According to Capt. Don Goulet, Estabrook on Tuesday was waiting for statements from the town officials involved, who have the option of applying for protection from harassment orders against the man making the threats.

Staton, who has a sign calling for the ouster of Libby in his yard, was accused in 2012 of threatening the local animal control officer, informing others that the officer “is on my kill list.”

At the town fire station, an official said firefighters had received death threats from the man around the same time. Other references to a “kill list” were said to have been used during the threats against Libby this month.

According to Maine law, a person is guilty of criminal threatening if he “intentionally or knowingly places another person in fear of imminent bodily injury.”

According to court records, Staton was convicted of criminal mischief in 1999. Attempts to reach him Tuesday were unsuccessful.