San Francisco trains hit by systemwide outage

San Francisco's main public transport system abruptly shut down Friday morning, stopping all trains in the Bay Area and throwing the morning commute into chaos.

"Due to a computer networking problem BART service is suspended system wide until further notice," said a message on the Bay Area Rapid Transit website.

"Seek alternate means of transport."

The shutdown left tens of thousands of commuters scrambling to find other ways to work.

Pictures showed crowds of people pressing aboard buses, while reports said both the Golden Gate Bridge and the Oakland Bay Bridge -- key routes into and out of the city -- were clogged.

Unlike many major US cities, San Francisco has a well developed public transport network that includes an underground train network, buses, trams and ferries that traverse the bay between San Francisco and other cities in the region.

The closure of the BART train system, whose 131 miles (210 kilometres) of track carry more than 174,000 passengers every day, appeared to be related to how the system had powered up after overnight maintenance, communications officer Alicia Trost told ABC7.

There was no immediate indication that the problems had been the result of a cyberattack, she said.

The halt caused misery for those trying to get to work.

David Meland told the San Francisco Chronicle he had waited in vain outside his local station for an hour to see if the service would resume.

"It’s happened a lot. BART’s just too inconsistent," he said. "This is pretty bad."

Patrick Dunn, who had driven to an exurban station to ride into the city said he was going to have to switch transport.

"Now I have to take the bus, and I never take the bus," he told the Chronicle.

"I already have a long commute and now I have to wait for the (bus). I’ll be late by an half hour or so."

The shutdown came on the day that the overstretched airport in Newark, one of three serving greater New York, also suffered an outage -- the second in the last few weeks.

The Federal Aviation Administration (FAA) said there "was a telecommunications outage that impacted communications and radar display" at the same Philadelphia traffic control station that guides aircraft in and out of Newark's airspace.

The outage occurred around 03:55 (07:55 GMT) on Friday and "lasted approximately 90 seconds," a short statement said.