Updated on Dec. 12:
A downed tree in the middle of the busy intersection of Muirwood Drive and West Las Positas is snarling traffic Thursday morning.
The traffic lights were on flashing red, so it was back to being a four-way stop pattern for drivers.
Witnesses say apparently a bus somehow hit the tree or tree limb, knocking it down. One reader reported that the collision took down a portion of the traffic signal.
The reader wrote:
"It landed on the bus above the front doors taking off the side mirror. The traffic signal is crushed to the ground."
Riders on the bus got off and were standing by the road. Pleasanton Police blocked off the intersection and by 8:35 a.m. the tree had been removed from the intersection while police conducted their investigation.
Pleasanton Police Sergeant Bob Leong said:
"It looks like the bus hit the tree limb which caused the limb to strike the signal light. Not sure if the limb was partially broken in the storm or not, but we do know that the driver never noticed the hazard and drove into it."
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