Ashley Guillory, 37, was driving a black 2005 Toyota Camry when she disappeared Sept. 4, according to Houston police.
Crews were searching the Missouri City/Stafford area Thursday.
According to Texas Equusearch founder and director Tim Miller, Ashley's case is now being investigated by HPD's homicide division.
"We've actually been kind of involved in this case for nearly a week," Miller said. "We worked with missing persons and now, homicide."
"We feel as though now, very possibly, very probably, foul play has been involved in the disappearance of Ashely," Miller added.
Since it has been nearly two weeks since she was last seen, and Hurricane Nicholas caused wet weather conditions, Miller said he fears the search could be difficult.
"We're now 11 or 12 days out, so time is not on our side," Miller said. "The other fear of course is we just got over the tropical storm where the waters came up high. Like anything we do, it's a process of elimination."
It is unclear what type or style of clothing Ashley was wearing when she disappeared.
If you have seen Ashley since her reported disappearance, if you know of her current whereabouts, or if you have any information whatsoever concerning Ashley's disappearance, please call the Houston Police Department at (832) 394-1840 or call Texas EquuSearch at (281) 309-9500.
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