Search and rescue crews are searching the area of Crestone Peak in the Sangre de Cristo Mountain Range for a hiker who has been missing since Sunday.

Jason Pettigrew, 29, of Denver left Sunday planning to climb two 14,000-foot mountains -- Crestone Peak and Kit Carson Peak. He was supposed to descend on Monday but a friend called the Custer County Sheriff's Office saying that he had not returned.

At least 43 people from seven different agencies are involved in the search effort. A Black Hawk helicopter was searching Wednesday when inclement weather grounded it. Another helicopter from the National Guard out of Eagle is involved in the search Thursday, said a spokesperson for the Custer County sheriff.

Pettigrew said he was going to climb Crestone Peak first and then Kit Carson Peak, but officials do not believe he ever made it off the first peak.