A woman who was reported to have been attacked with a knife at a music hall near Tokyo on Thursday has admitted that she stabbed herself, police have said.

The 48-year-old woman told police in Kanagawa Prefecture that she stabbed herself in the abdomen with a kitchen knife she had brought from home. The woman was quoted as saying that she has been dealing with worries.

The woman's injuries were minor, and she has already been released from the hospital, the police said.

The woman, from Osaka Prefecture, went with her husband to a music event held at the K-Arena Yokohama facility in the Minato Mirai waterfront district of Yokohama on Thursday.

Initially, she told police that she noticed something like a knife stuck in her abdomen outside of the music hall.

Her confession came during further questioning, after police investigators could not find any suspicious person on security camera footage or any witness to what she initially claimed to have happened to her.