SARASOTA, Fla. -- An unemployed mechanic with a criminal record refused to answer questions about the whereabouts of an 11-year-old girl he is suspected of abducting outside a car wash in range of a surveillance camera.

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South Florida authorities said Thursday that "strong evidence" links 37-year-old Joseph Smith to the kidnapping of Carlie Brucia, a 6th-grader seen on the camera's tape being led away by the arm Sunday. The man is seen talking to the girl, who doesn't appear to know him.

Authorities believe Smith (pictured, below right) is the tattooed man in a mechanic's shirt on the tape, but he has not been charged with a crime. He was taken into custody on a tip from a woman who lives with him and is being held on unrelated charges.

"He has not been formally charged, however there is no bond on the unrelated charges that we have on him," Sheriff Bill Balkwill said. "Formal charges will be filed at the appropriate time as we continue to build our case for prosecution," Balkwill said.

The sheriff's office received more than 400 leads from citizens.

Investigators are searching for a pink backpack Carlie was carrying when she disappeared and urged TV stations to continue showing images of Smith's car, a Buick Century station wagon.

"We are certain that the '92 Buick station wagon that we have is the vehicle used in the abduction," Balkwill said.

Law enforcement officers say Smith, who has been convicted previously on felony drug charges, is not cooperating with authorities in Carlie's disappearance.

The girl's whereabouts are not known. A private investigator hired by the Brucia family says that relatives headed to what was described as "a crime scene" Wednesday night, according to The Associated Press. However, Sarasota sheriff's deputies would not confirm that.

Balkwill asked the media to be careful because there are many rumors about the case.

State records show that Smith has been arrested at least 13 times in Florida since 1993. He was arrested in 1997 on kidnapping and false imprisonment charges -- but was acquitted a year later. Other arrests range from misdemeanor battery to felony drug possession charges.

Smith's Neighbors Surprised By Arrest

Smith's neighbors, Ron and Linda Thompson, said they're shocked by Smith's arrest, but concede that the man seen on the videotape looks like him. They said he has children and is always "great" with them.

Linda Thompson said that Smith has never shown a dark side.

Members of Carlie's Girl Scout troop passed out fliers and pink ribbons Wednesday. One of them said, "I don't feel too good about this, knowing my best friend is out there with a stranger."

Carlie, who is about 5 feet tall and 120 pounds, has blond hair and blue eyes. She was last seen wearing a red top and blue jeans, and carrying a pink backpack.

Even NASA has been involved in the search for the girl. The FBI has been working with the space agency to enhance images from a surveillance camera that captured the child's abduction.

Meanwhile, authorities are awaiting enhanced video images from the security camera that captured the abduction.

A national hot line has been established to gather information. Two experts from The Center for Missing and Exploited Children are assisting, distributing 16,000 flyers with Carlie's picture throughout the region.

Anyone with information on Carlie Brucia's disappearance can call (888) 382-6237, (800) 843-5678 or (941) 861-5800.