SAN FRANCISCO (KRON) — Residents living in San Francisco have been calling to complain about the smell of gas in part of the city Wednesday morning.

PG&E and fire crews are working to find the cause of the strange smell.

At least 30 individuals called PG&E reported a smell of rotten eggs or sulfer throughout the city, including the neighborhoods Nob Hill, Tenderloin, Bay View and Mission.

PG&E received the most calls about the smell at around 2 a.m.

As of 7 a.m., the odor has dissipated and no cause or origin has been determined.

One possibility that PG&E is looking at is that the smell could be caused by the earthquakes in Lake Tahoe. The earthquakes may have caused the ground to shift and release a sulfur-like smell into the air.

Several people also reported feeling ill due to the smell but their symptoms are unknown at this time.

Officials say there is no threat or safety concern at this time.Stay with KRON4 News for updates