UPDATE: The Transit Center has reopened, and the substance that had caused the closure turned out to be sheetrock powder, a Santa Clara County sheriff's captain said.
A bus operator on Route 22 that started at Eastridge Transit Center in San Jose reached the end of the line in Palo Alto and saw a white powder about the size of a finger while sweeping through the vehicle, sheriff's Capt. David Lera said.
While fire personnel could not identify the substance, Santa Clara County fire crews were also called and utilized more "sophisticated" equipment, Lera said.
Shortly before 11:30 a.m., they determined the substance was sheetrock powder that possibly came from a worker's pants, according to Lera.
The bus loop at the transit center was evacuated but Caltrain continued normal operations, Lera said. No injuries were reported, adn there was no indication of any criminal intent associated with the incident, Lera said.
Palo Alto's Transit Center is closed on Thursday morning due to a suspicious substance found on a bus, a Santa Clara Valley Transportation Authority spokeswoman said. Buses will not be stopping at the transit center and are being diverted to the Stanford bus stop in front of Stanford Shopping Center on El Camino Real, she said.
A bus driver discovered a suspicious substance on the seat of a bus and called for emergency responders at 7:40 a.m. to investigate, VTA spokeswoman Stacy Hendler-Ross said. There were no passengers on board and no one experienced effects from the substance.
The Santa Clara County Sheriff's Department, which has jurisdiction over the transit center at 95 University Ave., called in the Mountain View Fire Department's hazardous materials team. Palo Alto police are assisting with traffic control.
The hazardous materials team was not able to identify the substance and members were donning special suits at about 9:45 a.m. to remove the substance from the bus for further testing, Hendler-Ross said.
Bus lines 22 and 522 are rerouted as follows, according to VTA:
From El Camino, buses will turn left on Quarry Road, right on Arboretum Way, right on Sand Hill Road, right on El Camino. Scheduled buses for boarding on El Camino Real at Quarry Road-Stanford Shopping Center will stop prior to Quarry Road.