President Donald Trump is at it again, this time using popular social media site Twitter to take aim at former friend and mentee, Omarosa Manigault Newman.

Trump is following up his off-the-cuff insult toward the former Director of Communications for the Office of Public Liaisons, where he called Newman a “lowlife” during a photo opportunity with a group Bikers for Trump in New Jersey last weekend.

The president is now doubling down, calling the former Apprentice cast member, “crazed,” “deranged,” and a “dog” for claiming to know of recordings where he can be heard using the n-word.

“@MarkBurnettTV called to say that there are NO TAPES of the Apprentice where I used such a terrible and disgusting word as attributed by Wacky and Deranged Omarosa. I don’t have that word in my vocabulary, and never have. She made it up.”

Trump goes on, “Look at her MANY recent quotes saying such wonderful and powerful things about me – a true Champion of Civil Rights – until she got fired. Omarosa had Zero credibility with the Media (they didn’t want interviews) when she worked in the White House. Now that she says bad about me, they will talk to her. Fake News!”

A few hours later, Trump hopped back on to drive the nail into the coffin.

“When you give a crazed, crying lowlife a break, and give her a job at the White House, I guess it just didn’t work out. Good work by General Kelly for quickly firing that dog!”

See the tweets below.

According to Newman, President Trump is a certified “racist” who uses the n-word on a regular basis. The Guardian reports she claims Trump was caught on mic using the racial slur “multiple times” during the making of The Apprentice, according to three unnamed sources within her new memoir, Unhinged: An Insider’s Account of the Trump White House.