Police questioned and released Saturday a man who reportedly had contact with a 14-year-old girl abducted from her bedroom earlier this week, ruling him out as a suspect in the case.

The questioning, which followed police distribution of a sketch of the man, proved to be yet another fruitless lead in the investigation.

"We were hoping it would be something we could hang our hats on. But that's OK. We'll move on," Salt Lake City Police detective Dwayne Baird said. The man had no known criminal record.

While about 100 detectives follow up on the thousands of potential leads being called into the Salt Lake City Police Department, the Smart family asked volunteer pilots to coordinate an air search Saturday.

About a dozen pilots responded to the request and took to the air Saturday afternoon.

"We believe that Elizabeth is alive. We feel in our hearts that we know she is alive. That is a very strong thing," Tom Smart said. "She's somewhere. Check your basements. Check your houses."

While about 100 detectives follow up on the thousands of potential leads being called into the Salt Lake City Police Department, the Smart family asked volunteer pilots to coordinate an air search Saturday.

About a dozen pilots responded to the request and took to the air Saturday afternoon.

"We believe that Elizabeth is alive. We feel in our hearts that we know she is alive. That is a very strong thing," Tom Smart said. "She's somewhere. Check your basements. Check your houses."

The girl was reportedly kidnapped at gunpoint between 1 and 2 a.m. Wednesday in front of her frightened younger sister. 

Elizabeth, described by friends and family as a quiet girl, was wearing short red satin pajamas. Police said the kidnapper allowed her to put on white canvas tennis shoes before she was taken away from her wealthy Federal Heights neighborhood.

The description of the man wanted for questioning proved to be another dead-end in case that, so far, has had only dead-ends. Earlier, police had expressed dismay that none of the hundreds of tips they'd received pointed to a particular suspect in the abduction.

"I am frustrated," Salt Lake Police Chief Rick Dinse said at a news conference Friday.

Police believe an intruder forced open a window of the Smarts' house early Wednesday morning and woke the teenager and her 9-year-old sister.

The terrified younger girl waited two hours before alerting her parents because the gunman threatened to hurt her sister if she told anyone right away.

Elizabeth's sister has not been able to clearly describe the man, telling police only that the kidnapper carried a small black gun and was about 5-foot-8, white, with dark hair, dressed in a tan denim-type jacket and white baseball cap.

Dinse said police have some evidence an intruder was in the house, though he wouldn't reveal it. He also refused to discuss the conversation the intruder had with the sister before taking Elizabeth.

The police chief also expressed frustration with the crime scene. He said at least 10 of the Smarts' neighbors were invited into the house before police could arrive at 4 a.m. Wednesday.

"Everyone is still a suspect," Atkinson said. The family is not the focus of the investigation, police said.

Elizabeth's father, Ed Smart, was released from a hospital in good condition Friday after collapsing from exhaustion. He had slept little in the hours since his daughter's disappearance.

Sheriff's deputies on Friday questioned the credibility of a volunteer searcher who said he spotted a man matching a description of the intruder and acting evasively in the woods at the top of Emigration Canyon, just east of Salt Lake City.

An all-night search yielded nothing, and sheriff's spokeswoman Peggy Faulkner said the volunteer and his twin brother were wearing fake law badges.

Police discounted another lead Friday from the manager of a convenience store two miles from Elizabeth's house who produced a videotape from his store's security camera. Police said the man shown on the tape wasn't a suspect.

The Associated Press contributed to this report.