Federal prosecutors Thursday accused a northern Michigan man of threatening to kill one of the attorneys for the whistleblower who spurred the impeachment inquiry of President Donald Trump, according to federal court records.

Brittan Atkinson, 52, of Beaverton, in northern Michigan, emailed the lawyer in November, writing, "All traitors must die miserable deaths. Those that represent traitors shall meet the same fate," according to the indictment unsealed in federal court. "We will hunt you down and bleed you out like the pigs you are.

"We have nothing but time, and you are running out of it," the email continued. "Keep looking over your shoulder(.) We know who you are, where you live, and who you associate with(.) We are all strangers in a crowd to you(.)"

The lawyer is not identified in the indictment but attorney Mark Zaid of Washington, D.C., confirmed to The Detroit News that he received the email. The email was sent one day after Trump criticized Zaid and the attorney's tweets during a rally in Louisiana.

"I hope this indictment sends a message to others that such behavior will not be tolerated by a civil society that is governed by law," Zaid wrote in an email to The News. "It's not appropriate for anyone to threaten another individual's life, regardless of political views.

"My job was to ensure the rule of law was followed in how whistleblowers are treated," Zaid added. "That role should not be negatively weaponized by partisans."

The indictment was unsealed after months of attacks by Trump and GOP allies, attacks that included describing people who might have talked to the whistleblower as “close to a spy” along with suggestions they engaged in treason, an act punishable by death.

In December, Trump retweeted a post that included the alleged name of the anonymous whistleblower whose complaint ultimately led to the president's impeachment by the House.

Zaid's identity as the lawyer referenced in the Atkinson indictment was reported earlier Thursday by Politico.

The whistleblower’s complaint raised alarms about Trump’s dealings with Ukraine, alleging that the president abused the power of his office to “solicit interference from a foreign country” in this year’s U.S. presidential election.

Atkinson, who public records show worked as a laborer foreman, made an initial appearance Thursday in Bay City and was ordered temporarily detained. A not-guilty plea was entered and a detention hearing scheduled for Monday.

The charge filed against Atkinson is punishable by up to five years in prison.

The Associated Press contributed to this report.