PHILADELPHIA (CBS) – Friends and family gathered Saturday to remember the life of 19-year-old Mark Keeley, the PGW first responder who was killed in a gas main explosion earlier this week.

Last Tuesday, Keeley died while responding to a leak in a high pressure gas main in the Tacony section of Philadelphia. The main ruptured, injuring four other PGW first responders and a Philadelphia firefighter.

Keeley was a 2009 Cardinal Dougherty High School graduate and followed the footsteps of his father who has worked at the gas company for nearly two decades.

There are still plenty of questions about the gas main that ruptured. PGW says the main is 71 years old but does not have a record of problems. In every neighborhood across the city, PGW is facing old gas lines, some dating back to 1898, that are getting older by the day.

As a sign of respect, Mayor Nutter requested that all city flags be lowered to half-staff until after funeral services for Keeley who leaves behind his parents, grandparents, three siblings, and several other relatives.

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