INYO COUNTY, Calif. (KSEE/KGPE) – Crews are still searching for a man who was last seen hiking up a mountain last week in Kings Canyon National Park, according to the Inyo County Sheriff’s Office.

66-year-old Quang Trong Than was last seen near the peak of Split Mountain, located on the crest of the Sierra Nevada, between 3:00 p.m. and 4:00 p.m. on Sunday, August 21.

Quang had been hiking with two other people when the group left the Red Lake trailhead to climb the north slope of Split Mountain. The group planned to take a day hike up to the summit and leave later that night, so Quang didn’t bring any equipment for staying overnight.

At 13,200 feet up the mountain, officials said one of the hikers stopped and waited for about an hour for Quang and the other hiker to catch up.

Investigators said Quang ended up waving on the hiker who was waiting for him, possibly indicating that he was either going to fall behind, wait for them there, or head back down the mountain.

Quang Trong Than was last seen wearing the same gear he had on in this photo.

Investigators said Quang and the group never specified to each other what he was planning to do after telling them to go on ahead without him.

The two hikers returned back to their car around 3:30 a.m. Monday, but they didn’t find Quang there waiting for them.

Quang had left a red jacket and a helmet at Red Lake to grab after the hike up Split Mountain, but officials said he never returned to pick them up.

The following day, search and rescue crews from multiple law enforcement agencies began combing throughout the area for Quang but have not found any sign of him.

Authorities have been searching through the area on the ground, and by air using helicopters equipped with high-powered optics.

While searching, crews said they spoke with another group of hikers who said they had gotten lost and ended up going toward the wrong gully on their way down the mountain. The group was able to turn around and get back on the path they needed to take to get back down the right way.

Quang is described as 5’2″, 145 pounds, with grey hair and brown eyes.

Anyone with information about Quang’s whereabouts is asked to call Kings Canyon National Park at (559) 565-4296, or Inyo County Sheriff’s Dispatch at (760) 878-0383.