A magnitude 4.3 earthquake struck the San Francisco Bay Area early Monday morning, centered near Berkeley, California. The quake, which occurred just before 3 a.m. PDT, was strong enough to awaken many residents and trigger sharp shaking in homes. Initially reported at magnitude 4.6, the United States Geological Survey later revised the quake’s strength to 4.3.  The epicenter was located just east-southeast of Berkeley, close to the University of California campus.

People across a wide area - including San Francisco, East Bay, and even cities farther away like Salinas, Stockton, and Santa Rosa - felt the trembling.  In many places, the earthquake set off phone alerts. Some alerts, however, came in late—after people already felt the shaking. Despite the jolt, there are no immediate reports of damage or injuries.  Pets were startled and small household items were apparently knocked over in some homes.

Geologists caution that minor aftershocks are possible. They also note that there is a small probability—about 5%—of a larger tremor occurring within the next few days after such a quake.