Trains were running through but not stopping at the 12th Street station, which was evacuated shortly after a bag left on a train was found to contain a cylinder-shaped device wrapped in tape at about 6:10 a.m., spokesman Linton Johnson said.
A station agent brought the bag to BART police, who brought in two bomb-sniffing dogs that "both confirmed something was wrong," Johnson said.
The Alameda County Sheriff's Office Bomb Squad and University of California, Berkeley Bomb Squad investigated the package, according to Johnson.
There were no delays as a result of the package, according to Johnson.
