By Elizabeth Landers CNN

(CNN) — The personal attorney for President Donald Trump apologized on Thursday after a thread of emails was released showing threats he wrote to a stranger on Wednesday night.

The emails, obtained by investigative news website ProPublica, are profanity-laced and threatening, and are sent from Marc Kasowitz, who is currently representing the President in a personal capacity in the ongoing Russia investigation. ProPublica declined to name the stranger who sent Kasowitz the emails, only describing him as a retired public relations professional.

"F*** you," Kasowitz said in response to the initial email, which advised the attorney to resign from representing Trump. "No good can come from this," the man said to Kasowitz at 6:28 p.m. The attorney sent his short and explicit response only five minutes later.

Kasowitz sent a second email a few minutes after that, telling the man, among other things, to "watch your back, bitch."

According to the emails, the man responded shortly thereafter, "Thank you for your kind reply. I may be in touch as appropriate."

Kasowitz then responded again, telling the man to call him and appearing to offer his phone number. "Don’t be afraid, you piece of s***," he added.

In the final email he sent, Kasowitz identified himself as Jewish and said he presumed the other man was of the same faith. "I already know where you live, I’m on you. You might as well call me. You will see me. I promise. Bro."

In a statement to CNN, Kasowitz’s spokesman Mike Sitrick said, "Mr. Kasowitz, who is tied up with client matters, said he intends to apologize to the writer of the email referenced in today’s ProPublica story. While no excuse, the email came at the end of a very long day that at 10 p.m. was not yet over."

"The person sending that email is entitled to his opinion and I should not have responded in that inappropriate manner," Kasowitz himself said in that same statement. "I intend to send him an email stating just that. This is one of those times where one wishes he could reverse the clock, but of course I can’t."

Trump’s personal lawyer: ‘Watch your back, b****’