Early-morning East Bay quake downgraded to 3.4

The United States Geological Survey downgraded the magnitude of an earthquake that rattled the Bay Area early Wednesday morning to 3.4 from 3.7.

The quake on the Hayward Fault shook the Bay Area near the state Highway 24 and 13 junction in Oakland at 4:42 a.m., and was followed by two minor aftershocks of 1.9 at 4:45 a.m. and 2.0 at 4:48 a.m.

BART is reporting that its trains are recovering from 20-minute delays systemwide as maintenance workers inspect tracks after the tremblor, according to transit officials.