WASHINGTON — The Marine Corps has issued a cease-and-desist letter to Rep. Duncan Hunter, R-Calif., for using the official Corps emblem and phrase on campaign mailers that link his likely 2020 opponent and two Democratic congresswomen to terror.

In a letter to Hunter obtained by NBC News, the Marine Corps Trademark Licensing Office tells the congressman, "It has come to our attention that your campaign is using the official USMC Eagle, Globe and Anchor (Emblem) and the phrase 'No Better Friend, NO Worse Enemy' (Phrase) as an integral part of your political campaign, namely, on at least one fundraising mailer to your constituents."

The letter, dated Tuesday, demands that Hunter's campaign "immediately remove the Emblem and the Phrase from its mailers, and, without limitation, from all other campaign materials including websites and other instances where the Emblem or the Phrase are being used. We also request that you provide us with a timetable as to your compliance with our requests."

Click here to read the letter.

A spokesperson for Hunter said that the Hunter campaign "was made aware of the concerns expressed and the request made by the U.S. Marine Corps not to include any of its copyrighted material in his campaign pieces."

"The campaign immediately complied and is taking all appropriate measures to ensure this matter is addressed appropriately and thoroughly."

The mailer, which some have already called Islamophobic, is written in Hunter's voice and targets Ammar Campa-Najjar, who ran against him in 2018 and plans to run again in 2020, and Democratic House members Ilhan Omar of Minnesota and Rashida Tlaib of Michigan — two of the congresswomen recently attacked on Twitter by President Donald Trump. The mailer calls them "radical democrats" who "want you to forget their anti-Semitism or Family-Terrorist Ties!"

Hunter adds, "But as a Marine I'll never forget the 1983 Beirut bombings and the 1972 Olympic murders!"

Hunter served in the Marine Corps from 2001 and 2005 and was deployed to Iraq. As a reserve officer from 2005 to 2017, he was recalled to active duty in Afghanistan, reaching the rank of major. He has represented the San Diego area in Congress since 2009, first in the 52nd District and then in the 50th.

He currently faces federal charges of wire fraud, campaign finance violations, falsifying records and conspiracy. He has pleaded not guilty to all counts and has argued the charges are politically motivated. In June, federal prosecutors alleged in court documents that Hunter had used campaign funds to pursue extramarital affairs with five women while in Congress.

Campa-Najjar said in a statement to NBC 7 San Diego, "The closer Duncan Hunter gets to his criminal trial, the more absurd his lies and racist attacks become. At this point, it's pretty clear that Congressman Hunter has lost all ability to tell the difference between right and wrong, fact and fiction."

In a statement to NBC News, Marine Corps spokesman Lt. Col. Stuart Fugler said, "The Eagle, Globe, and Anchor is a trademark of the Marine Corps protected by Federal law. In accordance with 10 U.S. Code § 7881, the seal and emblem should not be used in conjunction with any political activities."

"The Marine Corps is taking appropriate action to address the referenced mailers," Fugler said.

The letter closed by noting that Hunter is welcome to "simply and accurately state" that he is a Marine Corps veteran and offered Duncan an alternative "Marine Veteran" logo to use to indicate "pride in service."

Hunter's spokesperson said the campaign has always used the required disclaimer on campaign materials as required by the Pentagon. The disclaimer says, "Duncan. D. Hunter was a Major in the United States Marine Corps Reserve. Use of his military rank, job titles and photographs in uniform does not imply endorsement from the Department of Defense or the Marines."