PACIFICA (CBS SF) — A teenage boy was trapped under a boulder that fell from a cliff in Pacifica on Saturday, officials said.

Firefighters responded to a call for a cliff-side rescue near the 800 block of Palmetto Avenue about 5 p.m., North County Fire Authority spokesman Matt Lucett said.

A 13-year-old boy had been climbing on rocks near the beach when a large boulder came loose, trapping him and crushing his legs, Lucett said.

Using hydraulic rescue equipment, firefighters took about 90 minutes to lift the boulder and extricate the boy.

He was taken to San Francisco General Hospital with serious injuries.

(Copyright 2012 by CBS San Francisco and Bay City News Service. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)