An off-campus stabbing police say was fueled by gang rivalry at Cypress Hills' Franklin K. Lane High has raised safety concerns at the school.

Witnesses say tensions rose Tuesday after gang members boarded a Manhattan-bound J train after school. The packed train became the scene of a fight that led to a stabbing. Police say 17-year-old Clarence Davis, who was attacked with a 12-inch butcher knife, was taken to Brookdale Hospital in stable condition. His attacker remains on the loose, but authorities recovered the weapon.

Many students and parents are on edge about the possibility of more violent fights. However, the principal says gang problems are rare at the school, and security is on hand. Many neighbors agree, saying the school has distanced itself from its troubled past.