OAKLAND -- BART has resumed service through the transbay tube in both directions but delays are expected throughout the system for the evening commute following a destructive and suspicious early morning fire that halted service between San Francisco and the East Bay most of Thursday.
"We are up and running almost at full speed, which is a bit of a surprise to me," said BART spokesman Jim Allison.
Allison said the West Oakland station, where tracks were melted by a fast burning fire near the station, reopened at 3:45 p.m., at least an hour earlier than expected. BART will run an extra hour of direct service on the Fremont to Daly City line.
BART opened one track with a test train about 3:10 p.m. to make sure the system is sound, Allison said. Still, commuters should expect longer than usual wait times Thursday evening.
"The trains will not be traveling with the same frequency or speed as usual," Allison said.
Fire investigators are still probing the blaze, sparked shortly after 2 a.m. Thursday at a construction site at 5th Street and Mandela Parkway. Just minutes before the fire, a security guard was attacked and forced to flee by three men at the site, according to the guard's employer.
The condition of the security guard was not immediately available.
"He saw three people coming to the construction site who looked suspicious, coming from the Kirkham Street side," said Kim Newbill, an office manager at Command International Security Services. "They said to him, 'What are you doing here?' He told them to move along and at that point, one guy went to jump over the fence to get in."
One of the men brandished something in his hand, Newbill said, but the guard couldn't tell what it was and ran to a nearby Subway sandwich shop for help.
When he saw flames rising up from the site, about 15 minutes later, he ran back to the on-site trailer where his cell phone had been charging and called 911, Newbill said.
The site is home to a new five-story senior housing facility called Red Star Senior Apartments. About $250,000 in new doors to be installed at the 172,000-square-foot site had been delivered recently, officials said.
The wood frames of all five floors burned quickly, officials said. The heat was so intense that several nearby streetlights and signs melted.
Several hot spots remained Thursday and investigators have not ruled out arson. Oakland fire officials are asking that anyone who saw something before the fire started to call investigators at 510-238-4031.
BART staffers had been planning Thursday morning to conduct a drill simulating an earthquake that rattled train service. It was canceled when the real-life crisis struck.
To repair damage from the three-alarm fire, crew replaced a section of the third rail between 350 and 400 feet long at the West Oakland station, Allison said. Thirty to 40 insulators holding up the rail were damaged in the fire, Allison said.
Traffic approaching the Bay Bridge was backed up most of the morning on all major East Bay routes to the Bay Bridge: Highway 24 and Interstates 80, 980, 880 and 580.
BART train ridership across the transbay tube is about 184,000 commuters on weekdays, about half of the system's overall ridership, officials said. Finding other ways to move that many people was a challenge.
Ferry service from Alameda and Oakland to San Francisco was boosted Thursday morning, carrying at least four times as many passengers as usual, said ferry spokesman Ernesto Sanchez.
In fact, Internet traffic to the ferry service's website at www.eastbayferry.com was so heavy it crashed the site, though the service phone number was still operating at 510-769-5500.
The Vallejo Baylink Ferry saw a 50 percent jump in ridership, officials said.
AC Transit stepped in to help, putting into service 20 to 30 additional buses to pick up evening commuters bound for the East Bay at the Transbay Terminal at Beale and Howard streets in San Francisco, said AC Transit spokesman Clarence Johnson.
Those extra buses will drop passengers off at the MacArthur BART station.
More information is available at www.actransit.org.
Marcus Hidalgo, a South Bay resident who works at a law firm in the Financial District, was scheduled to be at work at 9 a.m. He was hoping his boss would contact him and tell him not to bother coming in, as he had already driven from his usual BART stop in Fremont to Fruitvale to catch a bus, dealing with horrible traffic on Interstate 880.
"It was a parking lot on 880 the whole way," Hidalgo said. "I can't believe I subjected myself to this."
In downtown Oakland Thursday morning, about 100 displaced BART commuters waited in a line at an AC Transit bus stop near 20th Street and Broadway. The line snaked around the block and some waited for 90 minutes for a seat on a bus that would take them to work.
Mary Hartlund, a commuter who boarded BART in Walnut Creek and got off at the 19th Street station in Oakland, waited in the long line, hoping to get to San Francisco. "I don't see any buses," she said. "It seems they don't have the number of buses going that they should. It's going to be a long day and then we have to figure out how to get back."
The construction site where the blaze broke out is the former 1.5-acre Red Star Yeast manufacturing plant. Oakland's former redevelopment agency purchased the site for $2.75 million in 2008. Against the wishes of a leading community group, the city worked with nonprofit developer National Affordable Communities Inc., to transform the site into a 119-unit affordable housing complex, called Red Star Family Apartments.
Staff writers Matthew Artz, Harry Harris, Chris De Benedetti, Jeremy Owens, Angela Woodall, Denis Cuff, and Erin Ivie contributed to this report.