Los Angeles police said they have opened an investigation into rape allegations made against US actor Armie Hammer.

Hammer is the main suspect in a sexual assault that was reported to police on February 3, LAPD spokesman Officer Drake Madison said on Thursday. Police would give no further details on the incident or who made the report.

Earlier Thursday at a video news conference, a woman said that on April 24, 2017, in Los Angeles, Hammer raped her for four hours, slammed her head against a wall and committed other violent acts against her.

The woman appeared on camera but identified herself only by her first name, Effie.

Hammer's attorney denied the allegation.

"I thought that he was going to kill me"

The woman recounted the way she said she was "mentally, emotionally and sexually" abused by Hammer over the course of their four-year on-off relationship.

“During those four hours I tried to get away but he wouldn’t let me,” she said through tears. “I thought that he was going to kill me. He then left with no concern for my well-being.”

The woman's attorney, Gloria Allred, said they had given evidence to Los Angeles police, including photos of Effie's injuries. Allred declined to say when they made the report, and would not confirm that it was the one made in February that the LAPD is investigating.

Effie was 20 when she and Hammer met on Facebook and began a relationship in 2016, and they had their last contact last year, Allred said.

Hammer's attorney said in a statement that from the beginning he has maintained that all of his interactions with Effie and every other sexual partner "have been completely consensual, discussed and agreed upon in advance, and mutually participatory."

The statement called her allegations “attention seeking and ill-advised” and said “her own correspondence with Mr. Hammer undermines and refutes her outrageous allegations.”

“With the truth on his side, Mr. Hammer welcomes the opportunity to set the record straight,” Andrew Brettler said.

The statement included a screenshot that Brettler said was a text message exchange in July of last year between Hammer and Effie, in which she expresses a desire for rough, forceful sex with him, and he responds by saying he no longer wants a relationship with her.

The 34-year-old actor was married at the time to television personality Elizabeth Chambers. They divorced last year.

Effie, who lives in Europe, said she met Hammer on Facebook in 2016 and fell in love with him. After the alleged rape, she said she had suffered traumatic flashbacks and had felt suicidal. She said she felt guilty about not speaking out sooner and hoped Hammer would "be held accountable."

READ MORE:Armie Hammer faces cannibalism, rape fetish accusations after DM leak

Crumbling career

Hammer first gained fame through playing twins in 2010’s “The Social Network,” and is best known for his starring roles in 2017’s “Call Me By Your Name” and 2013’s “The Lone Ranger.”

Most recently, Hammer starred in the Netflix remake of “Rebecca.” A sequel to “Call Me by Your Name” with Timothee Chalamet has also been in development.

Allegations of sexual violence in recent months have derailed Hammer's career.

Earlier this year, an Instagram account began posting screenshots of text messages allegedly from Hammer as far back as 2016. Allred would not comment on whether her client was behind that account, @houseofeffie.

When those text messages began appearing in media reports, Hammer called them “vicious and spurious online attacks against me.”

After those texts were published, Hammer departed the comedy “Shotgun Wedding,” in which he was to star alongside Jennifer Lopez, shortly before production was to begin. He soon after departed the Paramount+ series “The Offer,” about the making of “The Godfather.”

Hammer was also dropped by his agency, WME.