The accusation against the actor began with an anonymous online posting dated Feb. 15, in which the author accused the actor of sexually assaulting her in the '90s when she was working with him at a theater in Busan.

The actor's name wasn't revealed in the post but his initials were.

"The actors habitually and secretly committed sexual harassment against junior female actors. He was one of producer Lee's pupils and now is a popular comedy actor," the person wrote, referring to the disgraced stage director Lee Youn-taek, who made a public apology on Feb. 19 for sexual abuse.

"For me he is no more than a pervert, an evil (person) and a psychopath. Since the shocking incident, I have been in pain for 20 years and still receive psychotherapy. I hope he is punished in hell."

On Friday afternoon, some media reported that Oh is the man referred to in the post. Neither the actor nor his management agency were available for comments and did not provide any official response until Monday.

"As I was filming a movie up to Feb. 24, I thought it was my duty as an actor to complete the shooting and be at the scene to make fewer problems for the movie's production team."

"I feel very frustrated as a person and an actor going through this. I offer my sincere apology for taking time to ruminate over and say what I have to say," he said. (Yonhap)