When a man tumbled onto the tracks at a downtown Philadelphia subway station, one passenger leaped into action.

Surveillance video shows Alfred McNamee walking close to the edge of the platform Wednesday and falling to the tracks. Charles Collins jumps down to help McNamee up.

WPVI-TV reports that the 28-year-old Collins is recovering from a minor leg injury.

McNamee's injuries are more serious. He suffered a broken back, a shattered knee, broken ribs and a spleen injury that could require surgery.

Transit officials laud Collins' actions as courageous but warn against jumping on the tracks. They say witnesses should alert a cashier or police officer.

Collins says he's no hero and just let instincts kick in.

"I just saw him down and jumped down... just instincts," he told WPVI-TV. "I'm not a hero. I mean, people do the same thing," he said.