Methamphetamine (search) may have impaired the judgment and ability of a young couple to feel the cold weather when they became lost in a snowstorm and died of hypothermia, authorities said Friday.

Michael Wamsley and Janelle Hornickel, both 20, had enough methamphetamine in their systems to create confusion, hallucinations, hot flashes and anxiety, said Dr. Henry Nipper, director of toxicology at Creighton University Medical Center (search) in Omaha.

Investigators believe the couple died Jan. 5, the same day they called 911 more than five times from a cell phone trying to explain their pickup was stuck in the snow and they were lost in a rural area southwest of Omaha. The calls, however, had bounced off different cellular telephone towers, making it impossible to accurately trace their whereabouts.

At times during their calls, the couple appeared to make no sense.

A one point Hornickel, sounding frightened, told the 911 operator about people breaking up cars and putting the parts in trees. The operator said police were on their way as she tried but failed to get an accurate description of where Hornickel and Wamsley were.

Just how the couple wound up in the wooded area, pockmarked with small lakes and sand pits, was not fully known, but they could have been disoriented even before they got out of the truck, Sarpy County (search) Sheriff Pat Thomas said.

Wamsley's snow-covered body was found the next day. After intensive searching involving police and volunteers, Hornickel's body was found six days later, at the edge of a sand pit lake. Both were within two miles of the truck. They did not have coats on.

A small amount of methamphetamine also was found in the truck. Learning the couple had been using drugs was frustrating, Sarpy County Chief Deputy Sheriff Jeff Davis said.

"It makes you angry from a lot of aspects," Davis said. "Two people lost their lives. Two families are going through and will continue to go through a terribly traumatic ordeal. Secondary to that, we talked about the expense to taxpayers; the volunteers, the danger they were put in."

Investigators trying to find the source of the methamphetamine served a search warrant in Kearney early Friday and arrested a mother and son.

Judy Morel, 56, and Mica Morel, 19, were arrested on suspicion of possessing a controlled substance and drug paraphernalia, Davis said.

On the evening before they died, Wamsley and Hornickel had been stopped by police for traffic violations in Geneva, about 100 miles west of Omaha. The couple, both from Ord in central Nebraska, said they were lost, and the officer pointed the right way to Omaha. Geneva police officials have said the officer who stopped the couple didn't notice anything unusual about their behavior.

Hornickel was a junior at Creighton University in Omaha. She and Wamsley had dated about a year, and most recently they had worked at the same telemarketing company.