A fuel spill involving a truck has blocked lanes of southbound Interstate 880 in Oakland, leading to major delays, authorities said.

According to the California Highway Patrol, officers were called to the freeway near 29th Avenue around 8:10 a.m. following reports of a truck blocking the middle lane.

When officers arrived, they found the truck was leaking fuel, prompting a traffic alert.

At one point, all lanes of southbound 880 were closed. As of about 8:40 a.m., only the rightmost lane of southbound 880 is open through the area. 

It was not immediately known when all lanes would reopen.

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