A missing Danville girl’s bike has been found near the Golden Gate Bridge, and a large-search is under way for her Tuesday morning, a National Park Service spokesman said.

Allison Bayliss, 15, was last seen by her parents riding her bike around 8 a.m. Monday at San Ramon Valley High School, Danville police said.

Her parents later reported her missing, and Danville police said they considered her to be at-risk. A sheriff’s search-and-rescue team began a search for her.

At about 4:45 a.m. Tuesday, Bayliss’ family informed authorities that they had found Allison’s bike in the Battery East parking lot, just to the east of the bridge on the San Francisco side, National Park Service spokesman Howard Levitt said.

The area is now being searched by U.S. Park Police, park service rangers, San Francisco police and others, Levitt said.

Allison is described as white with blond hair, 5 feet, 8 inches tall and 130 pounds. She was last seen wearing a red zippered hooded sweatshirt and blue jeans.

Anyone with information on her whereabouts is asked to call 911 immediately.