SALT LAKE CITY - A woman who was trapped in her car in a steep Utah canyon for two days before a sightseeing couple heard her cries for help remained in serious condition on Friday, hospital officials said.

Utah Valley Regional Medical Center spokeswoman Janet Frank said she could not release any further information about 29-year-old Heather Blackwelder. Authorities said she crashed through a guardrail on Tuesday and plunged several hundred feet (meters) down Spanish Fork Canyon, just south of Provo.

The Utah County Sheriff’s Office said a couple who was taking pictures in the area on Thursday called police when they heard Blackwelder screaming for help. The office said that due to the thick vegetation and trees in the area, Blackwelder likely would not have been seen by less attentive passersbys and could have died.

Spencer Dryden and his girlfriend, Cleo Jackson, told the local Provo Herald newspaper that they were about to get back into their car after taking some photos and leave the area when they heard Blackwelder’s pleas for help. “I was hearing ‘Help,’ repeatedly over and over again. At first I thought it was kids playing in the woods,” Dryden told the newspaper. Dryden stayed with her as Jackson looked for better phone reception to call for help.

Medical personnel stabilized Blackwelder and she was flown to Utah Valley Regional Medical Center in Provo, about 45 miles (72 km) south of Salt Lake City, according to the Sheriff’s Office. “It definitely changes the way you look at life,” Dryden told the newspaper. “I feel like my life has been forever changed by saving the life of another person,” he said.