Five university students were arrested Tuesday on suspicion of attempting to grope a woman on a commuter train in western Tokyo, police said.

The suspects are 20-year-old sophomores at private Asia University and belong to the university's baseball team, residing in a team dorm. They denied the allegations, police said.

Tsuyoshi Wada and the four others -- Shintaro Higuchi, Kazuto Kogin, Kentaro Shitan and Kazunori Nagata -- are suspected of attempting to grope a 20-year-old office worker on a Tokyo-bound JR Chuo Line train between Kokubunji and Musashi-Koganei stations at around 8:15 a.m. Tuesday, police said.

The woman, a resident of Sagamihara, Kanagawa Prefecture, had been placed under police protection after being molested in a previous groping incident on the same train line at around the same time of day on Nov. 30. The officers arrested the five on the spot as they tried to touch her, police said.

The woman was quoted by police as saying the suspects were in the same group that had molested her previously.

Police alleged the students had agreed to specific roles among themselves -- some of them would grope her while others would be on the lookout or serve as screens so other passengers could not see what was going on.

While he was in high school, Wada was a pitcher who participated in the 2002 national tournament at Koshien Stadium.

In Tuesday's incident, Wada is suspected to have been the groper, putting his hand in his trouser pocket to touch the woman's leg, investigators said.

The arrests come on the heels of 15 members of the Kokushikan University soccer team being arrested Dec. 1 on suspicion of sexually assaulting a 15-year-old girl in June.