Japanese police have detained a 23-year-old man wanted for allegedly abducting a teenage girl and holding her captive in his apartment for two years.

Police said the girl, now 15, escaped from suspect Kabu Terauchi's apartment in Tokyo on Sunday while he was out shopping and called home from a pay phone. She disappeared two years ago from her home town in Saitama, near Tokyo.

Saitama police said investigators detained Terauchi on Monday near a forest west of Tokyo. He was bleeding from the neck from a minor self-inflicted injury.

Officials said Terauchi had recently graduated from university.

l told investigators that she escaped when her captor forgot to lock the door from the outside when he went out shopping in Akihabara, known as a district for technology and comic book geeks.

The girl was seen wearing a sweat suit and sandals in the cold weather while using a pay phone at a train station in Tokyo. Her mother reported the call to the police, who raided Terauchi's apartment early on Monday.

Police quoted the girl as saying that she spent most of the past two years in the apartment near Terauchi's university in Chiba, before moving to Tokyo last month. She was always locked up in the apartment and closely watched, but was not tied up. There were times she was taken outside the apartment but always with her captor and under close watch.

The girl's disappearance two years ago when she was just 13 years old, was major news in Japan at the time.