A bomb squad responded to the area of E. San Fernando and S. Second streets when a suspicious device was spotted under or near a vehicle at around 9:55 p.m., San Jose police spokesman Dirk Parsons said.
Officers evacuated several blocks in the business district while the bomb squad attended to the device, Parsons said.
After about three hours, police determined the device was not harmful and the scene was cleared.
No one was injured during the response, Parsons said.
The incident is still under investigation.