A young man was stabbed to death and a dozen other people were beaten or knifed at a rap-music concert in this New York City suburb, say officials who are contemplating a ban on such events.

Knives and pistols were apparently smuggled inside Nassau Veterans Memorial Coliseum before Saturday night's violence even though the 10,000 people who attended "Jam 88" had to pass through an electronic weapons check, police said.Investigators believe a gang of about a dozen people may have been responsible for much of the violence, which apparently occurred during chain snatchings and other robberies, Deputy Chief Otto Geiger said Sunday.