PLEASANTON -- A Foothill High School student did not return home after a night out Saturday, and police are considering her an at-risk runaway.

The family of 15-year-old Danielle Hammer contacted police after she did not return home at 9 p.m. as scheduled, Pleasanton police Lt. Jim Knox said. Police are actively investigating her disappearance, Knox said.

"Basically at this point, she's considered a juvenile runaway," Knox said. "She is considered at-risk."

Anyone with any information is asked to call the Pleasanton police department at 925-931-5100.

Rick Hurd covers breaking news. Follow him at Twitter.com/3rdERH.