A U.S. Secret Service agent assigned to protect former first lady Jill Biden accidentally shot himself in the leg at Philadelphia International Airport on Friday, authorities said. Biden was not in the area when the agent was injured during a 'negligent discharge' of his firearm Friday morning, Secret Service spokesman Anthony Guglielmi told The Associated Press. According to initial reports, the agent was traveling in an unmarked car when he accidentally discharged his gun shortly before 9 a.m., said Philadelphia Police Officer Tanya Little. Other law enforcement officers came to assist the injured agent, who was taken to a local hospital. He is being treated for his injuries and was in stable condition, Guglielmi said. Airport operations were not affected, said Heather Redfern, public affairs manager for the city’s Department of Aviation.