OAKLAND (CBS SF) – All lanes reopened about 8:20 a.m. Sunday morning on northbound Interstate Highway 880 in Oakland, more than three hours after a chain-reaction wreck blocked the freeway, according to the California Highway Patrol.

Two people suffered major injuries in the series of two crashes just south of 98th Avenue, the CHP said.

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Northbound lanes were initially blocked while the CHP investigated the crashes, and an alert for heavy traffic was issued. The two left lanes reopened about 7:20 a.m., and all lanes were opened an hour later.

The first collision happened at 5:08 a.m., when a Lexus with a flat tire in the far right lane was rear-ended by a box truck, said CHP Officer Herman Baza.

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Ten minutes later, a Ford sedan rear-ended the truck. There were four people inside the Ford and two were hospitalized with major injuries.  One of the injured had to be extricated from the car, Baza said.

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