VIDEO: The City of Philadelphia is honoring a hero who gave the ultimate sacrifice. First responders, family and friends gathered Monday morning to pay their respects to Philadelphia firefighter Lt. Sean Williamson. Williamson was killed in the line of duty on June 18 after rushing to put out a fire at a pizza shop in the city’s Fairhill section. The burned building collapsed on top of him about an hour later. The funeral mass was at Epiphany of Our Lord Church in South Philadelphia. Firefighters from as far away as France and Montreal, Canada are paying their respects and honoring the ultimate sacrifice of Williamson. It was a somber procession Monday for fallen Philadelphia firefighter Lt. Sean Williamson, a moving tribute bidding farewell to a local hero. Neighbors watched from a stoop at 11th and Jackson Streets in South Philadelphia.