Authorities in Houston are on the search for Maleah Davis, a 4-year-old girl who was reported missing Saturday night. Davis may been abducted by three men in a 2010 blue Chevrolet pickup over the weekend, according to the Houston Police Department, though they are entirely relying on information provided by the girl’s stepfather, Darion Vence.

Authorities said they are particularly worried for Maleah’s safety — not only because she may be in the hands of kidnappers, but also because she has endured significant health problems, including multiple brain surgeries, the most recent of which she underwent about a month ago.

She had been ill in the days leading up to her disappearance, Sgt. Mark Holbrook said at a news conference Sunday.

Holbrook acknowledged to reporters that Vence’s version of events includes significant gaps and a lack of detail, which is why the police department is calling on the public for help to inform the timeline.

According to Vence, he was driving to George Bush Intercontinental Airport Friday around 9 p.m with Maleah and his 2-year-old son to pick up the children’s mother, who was traveling home from Massachusetts. Vence said he heard a popping noise and pulled over to make sure he didn’t have a flat tire.

A blue pickup then pulled up behind them, Vence told authorities, and two men got out of the truck. One made comments about Maleah, Vence said, including that she looked nice and sweet. The other hit him in the head, Vence told authorities, knocking him unconscious. All three were abducted, Vence told police.

At some point, Vence said, he awoke in the back of the truck with both children. There were three other men in the vehicle. Vence then said he lost consciousness again. When he woke up the second time, he said it was about 6 p.m. Saturday and he and the 2-year-old boy were on Highway 2. Maleah was not with them.

Vence told authorities he tried to flag down help on the highway, but nobody would stop. He and the boy then walked to Houston Methodist Sugar Land Hospital, Vence said. They arrived around 10 or 11 p.m., Holbrook said during the news conference. They reported Maleah missing at the hospital.

Maleah’s mother, whom authorities have not identified, did not report Vence or the children missing, Holbrook said during the news conference. She arranged for other family members to pick her up from the airport, authorities said.

Holbrook told reporters that Vence is at home with family. He does not have a criminal record, Holbrook said. Maleah’s biological father, who also lives in the Houston area, has been contacted by authorities and is being cooperative, Holbrook said.

At the news conference, authorities shared a photo of the type of truck Vence described: a 2010 blue Chevrolet crew cab pickup. They also shared a photo of the car Vence was driving when the alleged abduction occurred, a silver 2011 Nissan Altima with Texas paper tags 330-92G9. The Nissan belongs to Maleah’s mother, authorities said. She had just purchased it at a dealership.

Traffic cameras captured a photo of the Nissan driving through an intersection Saturday afternoon. It has not been seen since.

Authorities have not found any surveillance footage or witness accounts that corroborate Vence’s version of events.

“Darion doesn’t remember a 24-hour period of his life,” Holbrook said. “If somebody saw him, if maybe he was walking around in a daze, I’d love to know anything about that.”

When reporters at the news conference expressed skepticism about the veracity of Vence’s memories, Holbrook said authorities were relying on the public to aid the investigation.

“We’re hoping, the purpose of the press conference is to figure out what really is true, what really happened,” Holbrook said. “We don’t know. I just don’t know. And I don’t want to speculate.”

A small search party handed out 100 missing-person posters in a park in Sugar Land, near where Maleah allegedly disappeared, CNN affiliate KPRC reported. The group of five women, friends of Maleah’s mother, resumed their efforts Monday and were joined by Texas EquuSearch.

“She’s a spunky little thing, you know, and she’s beautiful,” Amber Fannin, a family friend helping with the search, told KPRC.

“She has a beautiful energy and we just want to find her at this point.”

Authorities issued an Amber alert that included a description of the outfit Maleah was wearing when she disappeared: a pink bow in her hair, a light-blue zip jacket, blue jeans and sneakers that are gray, white and pink.

Police encourage anyone with information to contact Houston Police Department Homicide at 713-308-3600 or Houston Crime Stoppers at 713-222-TIPS.

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