NEW YORK: The US Secret Service arrested a 72-year-old man in New York on Monday after he allegedly phoned them threatening to kill ex-president Donald Trump, a criminal indictment showed.

Prosecutors in Brooklyn say Thomas Welnicki "knowingly and willfully threatened to kill, kidnap, and inflict bodily harm upon" America's former president.

It alleges that Welnicki told US Capitol Police during an interview in July 2020 that if Trump "loses the 2020 election and refused to step down" he would "acquire weapons and take him down."

Trump is referred to as "Individual-1" in the indictment.

Welnicki is also accused of having left two voicemail messages with the Secret Service's office in Long Island, New York in January last year in which he "threatened to kill" Trump as well as 12 unnamed members of Congress.

"Oh yeah that's a threat, come and arrest me. I will do anything I can to take out [Individual-1] and his 12 monkeys," Welnicki, who lives in Queens, is alleged to have said.

Welnicki is also accused of having called the Secret Service's desk in New York City last November three times from his cell phone, introducing himself by name each time.

"He repeatedly referred to Individual-1 as 'Hitler' and stated, 'I will do everything I can to make sure [Individual-1] is dead," reads the indictment.

In another call last month he stated that "the new Civil war could break out and taking up arms against the government is justified when ballots don't matter."

He added that he used to own a .22 caliber firearm, according to the indictment.

Welnicki was due to be appear in a Brooklyn federal court via videoconference later Monday to be arraigned on the charges.