Derion Vence, the man who was watching 4-year-old Maleah Davis when she went missing, has been booked into the Harris County jail on suspicion of tampering with evidence, a human corpse, according to the jail website.
Police in Houston have not said whether a body has been found.
Investigators found blood evidence linked to Maleah in his apartment, police said in a Saturday news release
Vence, 26, was arrested Saturday at a relative's house in Sugar Land, southwest of Houston, police said. A court appearance is scheduled for Monday.
Police refer to Vence as Maleah's stepfather. A spokesman for the mother's family told CNN the two were engaged but that has ended. Police previously had spelled his first name as "Darion."
Vence has told police that last Saturday he was driving to the airport to pick up Maleah's mother and had Maleah and his 1-year-old son in his car. On the way, he heard a "popping noise," stopped his vehicle because he thought he had a flat tire and was knocked unconscious by three strangers who pulled up in a blue pickup truck, he told police.
When he woke up a day later, the boy was still there but Maleah was gone, he told police.
Vence's car, a silver Nissan Altima, was found two days ago in the parking of a shopping mall in Missouri City, Texas. Police said a laundry basket and a gas can were found in the trunk.
Vence had been seen carrying the laundry basket from his apartment, police said. They are asking for people who may know where the gas can was sold to contact the homicide division.
CNN has reached out to Vence several times this week, but didn't receive a reply. It's unclear if he has a lawyer.
Tampering with a human corpse is a second-degree felony in Texas, which if the defendant is convicted, is punishable by between two and 20 years in prison.
The-CNN-Wire ™ & © 2019 Cable News Network, Inc., a Time Warner Company. All rights reserved.