SAN DIEGO -- Office workers were evacuated Wednesday morning from the City Administration Building in downtown San Diego after smoke was seen coming from the high-rise, but the evacuation order was lifted when no fire was found.

Reports of smoke coming from the C Street building were received shortly before 7 a.m., according to a San Diego fire-rescue dispatcher.

By 7:15 a.m., firefighters had searched the building and deemed it safe for office workers, she said.

The smoke appears to have originated with a heating-air conditioning system, she said.