An earthquake outside of San Francisco shook people awake on Monday morning.
The U.S. Geological Survey said the earthquake struck a mile north of Piedmont, California, at 6:49 a.m. PDT. Originally reported as a magnitude 4.2, the earthquake was adjusted to a 4.0.
Piedmont is in the East Bay, 13 miles east of San Francisco, four miles from downtown Oakland and five miles southeast of Berkeley.
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Bay Area Rapid Transit briefly paused operations—standard procedure for the transit system—but all trains had resumed service by 7:25 a.m. PDT, according to a tweet from BART.
The Piedmont police said soon after the quake that there had not been any reports of damage.
The USGS reported at least six aftershocks near Piedmont, all under 2.5 magnitude.