A US Secret Service agent, working on security detail for the former first lady Jill Biden, shot themself in the leg at the Philadelphia international airport on Friday morning, an agency spokesperson said.

The Secret Service special agent suffered a “non-life-threatening injury” after they discharged their weapon at around 8.30am. Biden was not near the agent at the time and no one else was injured.

The agency’s office of professional responsibility will be investigating the “negligent discharge”, the spokesperson said.

“There were no reported injuries to any other individuals and the special agent is being evaluated at an area hospital in stable condition,” the spokesperson said. “We are grateful for our law enforcement and public safety partners who provided medical assistance.”

According to reporting from CNN, Biden went to the opening of an off-Broadway play on Wednesday called Public Charge, written by a former diplomat and former chief of staff to the first lady.