Joan Rivers calls Chelsea Handler a "drunk" and a "whore"

(CBS) Joan Rivers and Chelsea Handler are not holding back what they really think of one another.

Rivers reportedly called Handler a "drunk" and a "whore" during a radio interview with Howard Stern on Tuesday, after Handler told the radio show host "What the f--k do I care about Joan Rivers?" the day before.

The 78-year-old Rivers took Handler's question as fighting words and a day later fired back saying Handler "made it on her back, f--king the president [of E!]...we all know how she got there," according to The New York Post.

Rivers was referencing Handler's 4-year relationship with Ted Harbert, the former CEO of Comcast Entertainment Group, the parent company of E!, reports the Post.

River's continued her rant on Stern saying Handler is a "drunk" and warned the comedian, saying "Don't you come after me you whore."

Rivers was on Howard Stern with her daughter, 44-year-old Melissa. The two are in New York to promote the second season of their reality show "Joan & Melissa: Joan Knows Best?" on WE.