A crash involving an ambulance on southbound state Route 163 in Mission Valley is causing heavy traffic for morning commuters.
At least two vehicles, one an ambulance, were involved in the crash in southbound lanes near the Friars Road off-ramp at about 5:20 a.m., the California Highway Patrol said.
It was unclear if anyone was hurt.
At least two lanes were blocked, CHP said. At one point, only one lane of the freeway was open to traffic, NBC 7’s Whitney Southwick said.
"We’ve got a major slow down now. You want to avoid getting on the 163," Southwick said. "Traffic backed up all the way to Genesee and moving back towards the 805."
Traffic was still at a crawl more than two hours after the crash. Just before 6:40 a.m., all lanes were reopened.
No other information was available.
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