Sheriff’s and fire officials rescued a 19-year-old hiker Tuesday who was injured after falling into the Eaton Canyon Waterfall in the forest north of Pasadena, authorities said.

Eight other hikers who were with him, all between the ages of 15 and 19, were also escorted out of the forest just as it was getting dark, Los Angeles County sheriff’s Capt. Michael Parker said. None of the hikers, who were all Korean-speaking, had supplies or flashlights with them.

The group of nine hikers set out at about noon, officials said.

Around 5 p.m., just as it was beginning to get dark, the 19-year-old hiker, an El Monte resident, “fell down into a waterfall and was injured so badly he could not climb back up,” Parker said.

A member of the group then called authorities for help.

Sheriff’s and fire officials, with the help of a sheriff’s helicopter, found seven of the hikers together in a group, and another who had become separated from the rest and was lost, Parker said.

Rescuers hoisted the injured hiker from the waterfall and airlifted to a hospital with injuries not believed to be life-threatening.