Mountain biker sustains life-threatening injuries on Walnut Creek trail

WALNUT CREEK, Calif. - A mountain biker is in the hospital after crashing at Shell Ridge in Walnut Creek Sunday.

Fire and rescue crews flew a helicopter to rush the person to John Muir Medical Center. The cyclist sustained life-threatening injuries, officials said.

Photos from the accident show rescuers carrying the person on a stretcher. Two other cyclists looked on as they carried the stretcher away.

Officials did not give the name of the victim.

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