About 1,200 volunteers continued the search for a 14-year-old girl who was reportedly taken from her home at gunpoint more than 48 hours ago.

Authorities remain optimistic that Elizabeth Smart might still be found despite a lack of progress in the investigation.

"I don't believe we've gotten any leads that we could call really solid. Any at all," said Salt Lake Police Capt. Scott Atkinson.

Since Smart's disappearance became public, more than 1,000 tips have been given, with calls arriving at police headquarters at the rate of about one per minute.

One lead the police are still pursuing is the report from a milkman who saw a car in the neighborhood a day or two before the disappearance. According to his report, the milkman saw an older grey Nissan or Honda with a Utah license plate 266 RDA.

That plate didn't match any in the state's database, however, and permutations of the numbers and letters don't lead to cars fitting the description, Atkinson said.

Another lead set off a search early Friday of Emigration Canyon, a heavily-wooded area where a man fitting the reported description of the kidnapper was allegedly seen acting suspiciously.

A volunteer in the search said the man, who was wearing a white hat and a white shirt, could have been trying to wipe out footprints when he was seen on Thursday. The volunteer followed the man, but lost sight of him, and subsequently heard gunshots.

Friday morning, a SWAT team went back to the area to continue the search. The search continued into the night, with officials combing the area with search dogs.

There is at least one transient who lives in the area, sheriff's spokeswoman Peggy Faulkner said. Police say he is not considered a suspect but will be questioned if he matches the description of the kidnapper.

Elizabeth Smart's father, Ed Smart, was hospitalized on Friday for exhaustion after sleeping little since his daughter's disappearance.

According to police, between 1 and 2 a.m. Wednesday, an intruder forced open a window at the Smart home and entered the bedroom where Elizabeth Smart and her 9-year-old sister were sleeping. The intruder warned the younger girl that her sister would be harmed if she told anyone.

Because of the gunman's threat, the younger girl waited several hours before alerting her parents, police said.

The kidnapper did not call Elizabeth by name and he did not appear to know his way around the house, the sister told police.

The Associated Press contributed to this report.