Tragedy has struck the Penn State family this weekend, as a former backup quarterback was killed following a stabbing incident in Philadelphia.

According to Philly.com, Sean Schellenger was fatally stabbed during a traffic incident in Rittenhouse Square on Thursday night.

Per the report, Schellenger, who was a real-estate developer in Philly, was killed by a bike courier during a traffic dispute:

Homicide Capt. John Ryan said at a Friday news conference that Sean Schellenger had been with two other people in a Mercedes-Benz when the car got stuck in traffic on Chancellor around 10:50. All three men got out of the car in an effort to get a driver in front of them to move, Ryan said. The group then encountered a man on a bicycle, who may have been working as a courier.

Ryan said an argument ensued between Schellenger and the bicyclist, who pulled a large knife from his backpack as the struggle turned physical, stabbing Schellenger once in the back before running away.

Schellenger was 37 years old. He played at Penn State in 1999 and 2000, appearing in one game.

The suspect, 20-year-old Michael White, turned himself in to police on Friday, per the Philly.com report.