GLEN RIDGE, N.J. - Five male high school students, including twins who co-captain the football team, have been arrested in the sexual assault of a mentally retarded teen-ager.

The case sparked taunts, threats and incidents of vandalism at the school of 340 pupils in this community of 8,000 people about 20 miles from New York City. Thursday was the annual ``spring day`` at Glen Ridge High, and along with the picnics and games there were fights, car vandalism and graffiti scrawled on walls inside the school, students said.