FREMONT -- At least 20 cars were stopped --with about a half dozen of them sustaining flat tires, along southbound Interstate 680 at Mission Boulevard on Tuesday morning, after running over pieces of metal piping, according to the California Highway Patrol.
The first report of vehicles in trouble was made at 6:07 a.m., said Officer Kevin Bartlett.
It appeared the vehicles ran over pieces of metal piping causing flat tires to about five or six of them, Bartlett said.
Some of the cars were towed and others were repaired at the scene, he said.
The incident caused heavy traffic during the morning commute.
Officers were investigating how the piping got onto the interstate.