A man detained for touching a woman on a train was found dead near Ueno Station in Tokyo on Friday after fleeing from the station office where he was taken for questioning, the police said.

The man, described as in his 40s, was found lying beside a commercial building, and the police are investigating whether he fell from it.

The man was detained by East Japan Railway Co. (JR East) after a female passenger in her 30s complained that he grabbed her hand while sitting beside her on a Keihin-Tohoku Line train.

He slipped out of the office shortly before 1 a.m. while no one was looking, according to the police.

On the previous day, on the same line, a man in a business suit jumped onto the tracks from a platform at Shinbashi Station and ran away after a high school student complained inside a train that he had just groped her.

The incident was the latest in a string of cases where suspected gropers have jumped off train platforms to run away. The Shinbashi incident delayed dozens of trains and affected about 50,000 people because it occurred during the morning rush hour.

The man who fled from Shinbashi Station, however, appeared to be in his 20s or 30s, and was spotted running south toward Hamamatsucho Station, according to the police.