OAKLAND (CBS SF) — Fire crews have spent over eight hours trying to rescue a man who is trapped in a the ground next to a 10-foot sewer line in East Oakland, according to the Oakland Fire Department.

The independent contractor was working on a sewer line in the 2300 block of 21st Avenue when the trench collapsed on him at about 12:30 p.m., Oakland Fire Battalion Chief Coy Justice said.

Shortly after 9 p.m., rescue crews were still working to shore up the trench so they can safely remove.

Oakland Fire Deputy Chief Mark Hoffmann said the man is stable and communicating with rescue crews, but that one of his feet is lodged in clay-like mud. Hoffmann said the man’s head is approximately six to eight feet below the ground.

The man, who is about 50 years old, appears to be doing okay, Hoffmann said.

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