NBC senior political analyst, and frequent MSNBC “Morning Joe” panelist, Mark Halperin has just been accused of sexual harassment by five women who worked with him at ABC News in the early 2000s, according to a CNN report.

The veteran journalist is accused of having sexually harassed women while he was in a powerful position at ABC News, according to the women who shared their previously undisclosed accounts with CNN, and others who did not experience the alleged harassment personally but were aware of it.

Halperin did not deny the allegations.

“During this period, I did pursue relationships with women that I worked with, including some junior to me,” Halperin, 52, said in a statement to CNN Wednesday night. “I now understand from these accounts that my behavior was inappropriate and caused others pain. For that, I am deeply sorry and I apologize. Under the circumstances, I’m going to take a step back from my day-to-day work while I properly deal with this situation.”

MSNBC issued a statement early Thursday, saying, “We find the story and the allegations very troubling. Mark Halperin is leaving his role as a contributor until the questions around his past conduct are fully understood.”

Halperin was ABC’s political director at the time of the misconduct. According to the CNN report, the women, who asked to remain anonymous, accused him of kissing women without consent, grinding up against three women while pressing an erection against them, and grabbing one woman’s breast without consent.

None of the women involved reported Halperin to ABC management, and no quid pro quos were offered in terms of career advancement in exchange for sex.

“Morning Joe” co-host Mika Brzezinski addressed the matter not long after the show began on Thursday morning (see below).

“Now to a story that broke overnight involving someone you see around this table every day,” Brzezinski told her audience. “CNN is reporting allegations regarding our friend Mark Halperin during his time at ABC News over a decade ago, unnamed sources detailing unwanted advances and inappropriate behavior. Halperin apologized for the pain his actions caused and said, ‘I will take a step back from my day-to-day work while I properly address the situation.'”

She then promised to provide updates to the story as it unfolds.

Halperin rose to political stardom after co-authoring “Game Change,” which was based on the 2008 presidential election. The book was adapted into an award-winning HBO movie starring Julianne Moore as former Republican vice-presidential nominee Sarah Palin and Ed Harris as Sen. John McCain (R-Ariz.).