Eliza Dushku says she was sexually molested at age 12 by a stunt coordinator during production of the 1994 film True Lies.

In a post on her Facebook account on 13 January, the actor also alleged that Joel Kramer, then 36, caused her to be injured on the set as payback for disclosing the alleged misconduct to a friend. Kramer denied the accusations in trade publication interviews.

“These are outlandish, manipulated lies,” Kramer told the website Deadline. “I never sexually molested her … I think she’s making this up in her imagination.”

True Lies film-maker James Cameron said he was unaware of what he called Dushku’s “heartbreaking” experience and said she was brave for speaking up. “Had I known about it, there would have been no mercy,” said Cameron, who was taking part in a Q&A event with critics last weekend to promote a new TV show. “Now, especially when I have daughters, there really is no mercy.”

Dushku, who appeared in the TV series Buffy the Vampire Slayer and the film Bring It On, joins the growing ranks of those alleging sexual misconduct by men in the entertainment industry. The accusations against the movie mogul Harvey Weinstein, which he has denied, and other Hollywood and media figures gave rise to the #MeToo protest movement.

Dushku said at the time she told her parents, two adult friends and an older brother about what had happened, adding that no one “seemed ready to confront this taboo subject then, nor was I”.

She said the “ever-growing list of sexual abuse and harassment victims who have spoken out with their truths have finally given me the ability to speak out. It has been indescribably exhausting, bottling this up inside me for all of these years.”

Dushku alleges that Kramer lured her to his hotel room, put her on a bed and approached her naked except for a “flimsy” towel and rubbed his body over hers.

She confided to an adult female friend, who then allegedly confronted Kramer on the set. Dushku said that she then broke ribs in a stunt that went awry, calling it “no small coincidence”. She said Kramer “was responsible for my safety” on the film.

“This whole talk of luring her to my room, on top of her, getting off, holding her in the car and calling her jailbait is just outright hyperbole and lies,” Kramer told Variety in response to the allegations.

He said that Dushku’s accusations were “absurd” and added: “Who in their right mind would do something like that, when you’re a high-profile coordinator on a shoot like that with months left of shooting?”

Minors must be accompanied by a parent or legal guardian during production, but Sue Booth-Forbes, who was Dushku’s guardian on the set, says that she had failed to protect the child actor.

Booth-Forbes told Variety and Deadline that Dushku is “telling the truth,” and said she reported what she called Kramer’s “inappropriate sexual behaviour” at the time to “a person of authority” and that no action was taken. She did not identify the person to whom she reported the alleged incident.

Following Dushku’s allegations against Kramer, Worldwide Production Agency, who represent the stunt coordinator, said they are cutting ties with him. “WPA has elected to part ways with Joel Kramer based on the allegations of misconduct now being reported. Such behaviour is unacceptable and entirely at odds with the standards of conduct we demand of ourselves, and expect from our clients,” the agency’s president and general counsel Richard Caleel said in a statement to Deadline.

True Lies, starred Arnold Schwarzenegger and Jamie Lee Curtis. In an article on the Huffington Post, Lee Curtis wrote that the alleged abuse of Dushku shocked and saddened her.

“[Dushku] shared that story with me privately a few years ago. I was shocked and saddened then and still am today,” she wrote. “We have all started to awaken to the fact that the terrible abuses now commonplace in daily news reports have been going on for a very long time.

“Unconscionably, those reports frequently come along with claims by the perpetrators that, as adults, those perpetrated against had some part in it.”