Smoke surrounds plane at San Francisco International Airport

SAN FRANCISCO (KGO) -- Video, captured Thursday afternoon, showing smoke rising near an airplane.

United Airlines says there was no fire aboard an out-of-service aircraft.

The smoke began rising while the jet was being pushed outside a hangar where United performs maintenance work.

United also tells us smoke can rise from a plane due to residual oil in its engines.

A spokesman for SFO tells ABC7 News the incident is not affecting flights and that the airport is operating normally.