Seven men have recently been arrested in connection with alleged gang rapes in April involving a Waseda University student club, and four others already under arrest have been served fresh warrants, police said Wednesday.

Shinichiro Wada, 29, a former Waseda student who led the club, Super Free, and the others, mostly former or current university students, raped a female university student between 8:20 p.m. and 10:30 p.m. April 27 in a stairwell near a disco in Tokyo's Roppongi entertainment district, police alleged, without elaborating on the latest arrests.

The men allegedly got the 18-year-old student intoxicated by spiking her drinks with strong vodka at a restaurant after a party the club organized at the disco.

They took the girl to Wada's home in Toshima Ward and raped her again there, police alleged.

The club organized huge parties in famous discos and clubs in Tokyo, attracting women who wanted to meet men from elite universities.

Wada was initially arrested in June along with four other college students on charges of gang-raping another female student in May after a club party. All five were expelled from their universities following the arrests and the club was disbanded.

Thirteen men have now been arrested in connection with the rapes.