An earthquake with a preliminary magnitude of 3.3 rattled the Union City area on Wednesday evening, according to the U.S. Geological Survey.
The quake struck along the Hayward Fault, about 6:22 p.m., about 3 miles deep.
Another quake measuring 2.9 was felt earlier in the day in San Leandro, also along the Hayward Fault, at 8:34 a.m.
No damage has been reported.