The Houston Police Department, which joined Texas EquuSearch at Buffalo Run Park in the intensified search on Thursday, said the vehicle in the body of water is a truck and not the SUV that Hernandez was last seen driving.
In the search for Hernandez, police are looking for a 2020 GMC Black Acadia with Texas plates MKJ 3303 with an "Aggie Mom" decal on the back.
"It appears to be a truck and not the vehicle we were looking for. How it ended up there could be accidental, could be intentional. That's a part of an investigation," police said.
Volunteers have been searching wooded areas and HPD officers were searching using drones.
Information led investigators to that specific place in Missouri City.
Earlier this week, a banner with the words "Find Erica Hernandez" was unfurled on the Montrose bridges over the Southwest Freeway to help raise awareness about the case.
Congresswoman Sheila Jackson Lee, whom the family reached out to for help in increasing resources for the search, joined them after the banner drop.
"We can't imagine there's not someone out there with information, so the family is begging for people with any kind of information," Jackson Lee said. "We don't know what might've happened, but we know that she's a loving mother, and she has three beautiful children that want her to come home."
Electronic billboards also went up across the state.
The FBI is investigating Hernandez's disappearance, but there are no signs of her.
Her family, along with community volunteers, split up into groups and passed out flyers Sunday throughout Houston after search efforts were impacted by weather conditions for the second weekend in a row.
Family members said Hernandez is a single mother who works full-time to care for her three children. She even donates plasma twice a week, trying to bring in more money for her household.
Her son, Dennis, turned 16 years old last week. Hernandez's sister, Ashley Hernandez, said there's no way in this world his mom would miss his birthday.
"We still need to find her. That's the whole point, you know. Whether I think the outcome is going to be good or bad, we still need to find her and we still need her. We need her for her family, so I'm not exactly sure where their mind is at, but my mind is not in a good place," Ashley told ABC13.
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Hernandez hasn't been heard from since the early morning hours of April 18 when she left a friend's house in the 6000 block of Benning Drive in southwest Houston.
Family said Hernandez left her friend's home around 2:30 a.m. Sunday. She reportedly sent a text around 3:04 a.m. stating she was "five minutes away from getting home."
Ashley told ABC13 that detectives believe Hernandez was spotted near S. Post Oak and Court Road. That's where the family has turned the focus of their search and other routes that she may have taken to get home.
SEE ALSO: Texas EquuSearch looking for mom of 3 last seen in SW Houston on April 17
Anyone with information on Hernandez's whereabouts or her vehicle is asked to contact the HPD Missing Persons Unit at 832-394-1840 or Texas EquuSearch at 281-309-9500.
Her family is still raising money to continue search efforts through this GoFundMe page.
Family and friends are also providing search updates on the Let's Find Erica Hernandez Facebook page.
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