LOS ANGELES: Police in Los Angeles announced Tuesday they are investigating a rape allegation made against British "Gossip Girl" actor Ed Westwick.

Los Angeles Police Department official Drake Madison told AFP there was an "ongoing investigation" taking place, after actress Kristina Cohen accused him of rape Monday in a Facebook post.

"I do not know this woman. I have never forced myself in any manner, on any woman. I certainly have never committed rape," Westwick, 30, wrote on Twitter.

Cohen alleged Westwick raped her three years ago at his house, shortly after propositioning her and a producer she was dating.

"Ed insisted we stay for dinner. I said I was tired and wanted to leave, trying to get out of what was already an uncomfortable situation," she wrote, adding she was then persuaded to stay by the producer and went to rest in the guest room.

"I eventually fell asleep, I was woken up abruptly by Ed on top of me, his fingers entering my body. I told him to stop, but he was strong," she said. "I was paralysed, terrified. I couldn´t speak, I could no longer move. He held me down and raped me."

Cohen -- who has played roles in series such as "Californication" and "The Middle" -- added the producer blamed her and suggested accusing Westwick would ruin her career.

The accusation is the latest in a string of allegations of sexual misconduct in Hollywood, which follow the publication of an expose on movie mogul Harvey Weinstein in early October.