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Authorities are scouring ponds and lakes using high-resolution underwater imaging in their search for a 20-year-old nursing student abducted outside her rural Tennessee home.

A police spokeswoman told FoxNews.com Tuesday that law enforcement is searching underwater as well as in Natchez Trace State Park for any sign of Holly Bobo, last seen being led into the woods outside her Parsons, Tenn., home Wednesday morning.

Tennessee Bureau of Investigation spokeswoman Kristin Helm said a team of FBI agents and U.S. Marshals are also canvassing the woman's neighborhood, interviewing residents of the close-knit community for any leads in the case.

Bobo, a nursing student at the University of Tennessee at Martin, was last seen by her 25-year-old brother, Clint, who reported seeing her being taken into the woods at 7:30 a.m. Wednesday by a man dressed in camouflage. Clint told police that he initially assumed Holly was with her boyfriend, but said he grew concerned after finding blood outside, prompting him to call 911.

A police source confirmed to FoxNews.com that a "small amount" of blood was found in the family's carport, where Holly was believed taken from while on her way to school.

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Helm said investigators last week located the woman's lunchbox, found several miles from her home, as well as other items believed to belong to her.

"We do have some other things that we believe might belong to her, but [they] are undergoing forensic testing," Helm said.

As police continue their search Tuesday, a profile of the suspect has emerged. Detectives say they believe the alleged abductor may be from the area and possibly acquainted with Bobo and her family.

"We’re looking for someone who probably lives in that general area or is familiar with that area. If she was led into the woods, he would need to know the terrain to get in and out," Helm said. "It’s a very small community. If she didn’t know him directly, she may have been familiar with him."

Helm added, however, that "no one has been ruled out" as a suspect, and said police are looking for someone who may be showing "signs of stress or anxiety" or exhibiting "odd behavior."

She also noted that camouflage clothing, which the suspect is believed to have been wearing, is not an unusual sighting in Decatur County.

"Camouflage is very popular during turkey hunting season," Helm said. "It's a very common pastime here."

Police say they have received more than 300 "credible leads" so far in the investigation. Tennessee Gov. Bill Haslam on Monday approved a $50,000 reward from the state, making the total reward $75,000 for information leading to a suspect in the case.

Bobo's Facebook page says her interests include Miley Cyrus and country music singer Whitney Duncan, who is her cousin.

Friends said she loves animals, especially horses, and spends much of her free time going to dinner and the movies -- she likes "Morning Glory" and "The Hangover 2" on Facebook -- with her boyfriend.

Holly is described as 5-foot-3, weighing 110 pounds. She was last seen wearing a pink shirt and light blue jeans. Anyone with information on her whereabouts is being urged to call Tennessee law enforcement at 1-800-824-3463.

The Associated Press contributed to this report