As of 2:40 p.m. Thursday, BART reported major delays across the system due to an "obstruction" on the track in the Transbay Tube.

BART trains were single-tracking through the tube for approximately 30 minutes, which of course has a cascading affect on BART service in every direction. The nature of the obstruction still is not clear, but even after it was cleared around 3:07 p.m. this does not bode well for on-time trains as rush hour begins.

As of 3:13 p.m., Anna Duckworth in the BART communications office reported that the obstruction had been cleared and trains were again operating on two tracks through the Transbay Tube. "Expect residual delays as we recover," she said.