PHILADELPHIA (WPVI) -- A viewing was held Sunday night for the Philadelphia firefighter who was killed in the line of duty last weekend.
Lieutenant Sean Williamson, 51, died when a building came crashing down on top of him following a fire on June 18.
He was a 27-year veteran of the Philadelphia Fire Department who was most recently assigned to Ladder 18 in Hunting Park.
"As heartbreaking as it is, God knows how many people he saved by what he did by losing his life," said Giovanna Cavaliere of South Philadelphia.
Sunday marked the first of two viewings ahead of a funeral Monday. Members of Williamson's family arrived surrounded by a police escort. Co-workers of his son Pat said he and his father were as close as could be.
"They would have their cook-offs and he was very proud of his dad, so everyone is just giving him the support," said Toni Shepherd of Elverson, Pa.
Williamson was also a Marine and had served with other rescue agencies, including PA-Task Force 1.
First responders from other states came to pay their respects and remember a man who died trying to save others.
"Well we're all brothers, all firemen are brothers. They supported us during 9/11, we saw a lot of Philly patches," said Keith Nicolielio, with New York City Fire Department's Ladder 30.
Four other firefighters and an inspector with the city's Department of Licenses and Inspections were injured in the collapse that claimed Williamson's life.
The fire marshal's office is investigating the cause of the fire with assistance from the federal Bureau of Alcohol, Tobacco, Firearms and Explosives.
Williamson's funeral is set for 9 a.m. Monday. You can watch the service live on 6abc.com, the 6abc mobile app or the 6abc streaming TV app.