State police sent out a safety bulletin to law enforcement agencies last night after a Boston man posted a video to Twitter saying he was going to “take a gun” and “kill” police or EMTs.

Boston police have spoken to the man but he has not been arrested.

In the video, the man rants as he drives on what appears to be Route 24 behind a Brewster ambulance, which he claims is being used to harass him.

“So I get up to go to work and look who gets in front of me. The police using emergency vehicle to (expletive) with a (expletive) like me. But a (expletive) like me is going to take a (expletive) gun and kill one of these (expletive),” he says in the video, which was later removed.

The video post on Twitter was spotted by several people in law enforcement and emergency services personnel who forwarded it to the State Police Fusion Center as well as the Boston Regional Intelligence Center.

Based on that video, and several other comments and videos on the man’s account, state police issued a warning to law enforcement

“We sent out an officer safety bulletin to Massachusetts law enforcement agencies last night,” state police said. “We are investigating the threats.”

Last night at about 7:30 p.m. four Boston police located the man at a home in Dorchester.

“The suspect was asked why he was threatening to kill or harm police officers and he stated that it was his 1st amendment right to freedom of speech,” police wrote in the report. “The suspect then stated that he was reading how the police used to harass minorities in the 1960’s with fire engines and ambulances. The suspect then stated that he feels that every time he is at Target he is being harassed by the fire engines and ambulances.”

According to police, the man also said his car had been broken in to and he was angry that it took more than an hour to file a report at the Boston police station in area C-11.

“The suspect later Tweeted 3 short videos of the District 11 Lobby with #(EXPLETIVE)THEPOLICE.” police said.