OAKLAND, Calif. (AP) - A San Francisco Bay Area Rapid Transit train's emergency brakes malfunctioned Wednesday, stranding hundreds of passengers in a tunnel and sending at least nine people to hospitals, officials said.
Oakland Fire Battalion Chief Melinda Drayton said the nine were among 11 passengers who were treated for medical issues. The extent of their injuries was not clear, but Drayton said many of the passengers complained of respiratory problems caused by brake dust.
One passenger was found in a semiconscious state, and another suffered an asthma attack.
"No smoke, no fire. It was brake dust," Drayton told reporters at BART's Rockridge Station in Oakland.
"It was nerve-racking," BART passenger Kaylee Adams told reporters. "Everybody's trying to stay calm, everybody's trying to help each other, talk to each other and get through it."
The San Francisco-bound train stopped around 8:15 a.m. in the Berkeley Hills between BART's Orinda and Rockridge stations when the train's emergency brakes became "spontaneously engaged," BART spokeswoman Alicia Trost said.
The train emitted a white smoky substance that sickened some passengers, she said.
A technician was able to release the broken brake around 9:30 a.m., and the disabled train moved on its own power to the Rockridge station, where about 700 passengers onboard were evacuated with fire and medical crews waiting, BART spokeswoman Luna Salaver said.
The incident created significant delays on the line as the two stations were shut down. Full service was restored by noon with delays up to 15 minutes, BART spokesman Jim Allison said.
The nation's fifth-largest commuter rail service with about 400,000 weekday riders, BART has been plagued by problems in recent months, including two strikes by two of its largest unions.
Last month, a computer glitch shut down transit service during a Friday morning commute for hours. In October, a fire caused by a semiconductor box under the train's lead car at the Orinda station led to delays during a Wednesday evening commute.
Also in October, two BART workers were killed by a train operated by an employee undergoing training. The deaths occurred during BART's second transit strike in four months. The strikes shut down service and snarled traffic for thousands of commuters in the region.
On Tuesday, BART's two largest unions filed a lawsuit against the agency claiming its board of directors broke state law when it approved a contract two weeks ago without a key Family Medical Leave Act provision.
BART officials say the family leave provision had been inadvertently included in the tentative contract due to an error by a temporary employee, which led the board to approve the contract, minus the provision. The transit agency said the provision could cost up to $44 million over four years if one-third of union workers take six-week leaves each year.
The unions dispute that amount.
(Copyright 2013 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)