Secret Service
A US Secret Service agent stands guard as President Obama returns to the White House on the Marine One helicopter. Reuters/Jonathan Erst

The US Secret Service has launched an investigation into reported comments by Donald Trump's long-time butler, Anthony Senecal, that President Obama should be killed. "The US Secret Service is aware of this matter and will conduct the appropriate investigation," spokesman Robert Hoback said in a statement. Threatening the life of a president is a federal crime.

A Facebook post by Senecal calling for Obama to be "shot", alongside other similar threats, were discovered by Mother Jones magazine.

"To all my friends on FB, just a short note to you on our pus headed "president"!!!! This character who I refer to as zero (0) should have been taken out by our military and shot as an enemy agent in his first term!" Senecal wrote.

Senecal, 84, confirmed to the magazine that he wrote the posts. "I wrote that. I believe that," he said.

Senecal also admitted to CNN that he penned the post, but noted: "I think I said hung," apparently meaning "hanged." He was likely referring to an earlier post that read: "Looks like that sleezey bastard zero (O) is trying to out maneuver Congress again, if the truth be known this p--ck needs to be hung for treason!!!"

He added, in a phone interview with CNN: "Either way, I don't care. Hanging, shooting — I'd prefer he'd be hung from the portico of the White House, or as I call it, the white mosque," before asking "Does it sound like I'm nuts? Because I'm not," he said. "I've just gotten fed up with him."

The Trump campaign immediately distanced the candidate from the "horrible statements." Tony Senecal "has not worked at Mar-a-Lago for years, but nevertheless we totally and completely disavow the horrible statements made by him regarding the president," said campaign spokeswoman Hope Hicks.

Senecal told Mother Jones that he has been employed at Mar-a-Lago since about 1959. Trump acquired the property in 1985, and Senecal remained on staff.

As Trump says, "I came with the furniture," Senecal noted. About seven years later, he became Trump's butler, then asked to resign in 2009. He said Trump had persuaded him to stay on as the in-house historian at Mar-a-Lago. There is no salary for the job, Senecal said, but he makes money leading tours of the estate.

Senecal has posted several inflammatory comments on Facebook, including obscene attacks on Hillary Clinton, and claims on Facebook that the president is a Muslim, or as he says, a "Muzzie." He has also called for "carpet bombing" of the city of Ferguson, Missouri, which was wracked by protests after an unarmed black teen was killed by police.

He told the New York Times in March that he has never discussed his views with Trump, but enthusiastically supports his candidacy. He also said he spoke briefly with Trump in April.

"These are my ideas," he said. "They have nothing to do with Mr. Trump."

He said he agrees with the now-presumptive Republican nominee's call to ban Muslims from entering the United States. Common sense," Senecal said. As the candidate moves closer to the general election, however, Trump now says his strident call for a total "shutdown" on incoming Muslims was "just a suggestion."