A 42.5-ton block of concrete has blocked several lanes of southbound State Route 125 west of the Spring Street exit in La Mesa, California Highway Patrol officers said.
A tractor-trailer truck lost its load on the overpass just after 6 a.m. and prompted a SigAlert from the CHP.
Heartland Fire-Rescue crews responded and found no one injured. The driver was out of the truck, according to the CHP.
The semi lost its load and damaged a guardrail, officials said.
CHP officers called in a crane to remove the large block of concrete from the road.
They were able to drag the block off the overpass and to the side, where officials hope to lift it back onto the truck.
Shortly after the incident, officers closed all but one lane on southbound SR-125.
At around 11:30 a.m., all lanes were shut down, Caltrans said in a tweet. They reopened all lanes at around 3:45 p.m.
The road underneath the overpass, Panorama Drive, was also closed so engineers could determine if SR-125 was structurally sound.
No other information was available.
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