It happened in May along a walking trail in the Longwood Village neighborhood, but a sketch of the suspect has just been released.
The sheriff's office says the victim was walking the trails near the Longwood Golf Club/Little Cypress Creek area off Louetta Road when she spotted the man.
The teen told deputies the man allegedly turned around, pushed her down and then sexually assaulted her in a grassy area.
"That's a very sick, sick person. That's very horrible for the 15-year-old girl and her family," resident Elaine Smith said.
Authorities describe the suspect as a white man with an average build, gray hair and possibly a tattoo on his right arm, near his bicep.
Neighbors told ABC13 the area is popular for walkers and bike riders, and is usually a safe place.
"It concerns me a great deal that there's that kind of activity going on in this neighborhood. It's generally known to be a pretty safe neighborhood," resident Larry Wright said.
The man is now wanted for sexual assault of a child. Anyone with information about him should call 713-830-3250.
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