The remains of a child’s body were found Friday in Arkansas as authorities searched for a missing 4-year-old Texas girl who disappeared from Houston more than three weeks ago and who is thought to have been murdered, officials said.

The remains found have not been confirmed to have been those of Maleah Davis, the 4-year-old girl who was reported missing on May 4, officials stressed.

"I'm deeply saddened about what we are hearing," Houston Mayor Sylvester Turner said at a news conference Friday.

The remains were found in Arkansas after a local activist told the media that he had spoken with a man described as Maleah’s stepfather, who "stated Maleah’s body could be in Arkansas," Turner said. The man is jailed on a charge of tampering with evidence.

Houston Police said in a tweet Friday that homicide detectives were en route to Arkansas to assist local authorities in finding Maleah, who was reported missing by her mother's former fiancé Derion Vence. He has been jailed in connection to her disappearance.

Derion Vence was arrested Saturday by Houston police in the disappearance of his stepdaughter Maleah Davis, 4.

Sheriff James Singleton of Hempstead County, Arkansas, said earlier Friday that a black trash bag with a foul odor and containing blood was found in Fulton. Singleton said that it is still early in the investigation and it is not yet clear if the bag is connected to Maleah.

Police began searching in Arkansas after Quanell X, a civil rights activist who up until recently was a spokesman for Maleah's mother, said that Vence had confessed to him that he killed the girl and left her body along a road in Hope, which is about 13 miles from Fulton.

Quanell told NBC News that Vence told him Maleah's death was an accident and after allegedly killing her he drove roughly five hours to Hope, Arkansas, where he left the body on the side of a road.

Houston Police Executive Assistant Chief Troy Finner said Friday that Maleah’s family has been notified of the developments. He said that the only way that confirmation will be made is through an autopsy conducted by the medical examiner’s office.

"But do we believe that it’s possibly her? Yes," Finner said. "But can we confirm it right now? No. The main thing is: Pray for this family."

"We are here to make sure that this little angel receives some justice. And whoever’s responsible, we're going to hold them accountable," the executive assistant police chief said.

Houston police said Friday night that its homicide investigators were accompanying the remains of the child found in Arkansas to Houston, where an autopsy will be performed to determine the identity and the cause of death.

Vence, 26, was arrested on May 11 on charges of tampering with evidence, namely a human corpse, after investigators found a laundry basket and gas can in a vehicle he was driving the day he reported Maleah missing.

Vence had told Houston police that he was driving to the airport to pick up Maleah's mother, Brittany Bowens, when he was attacked by three men while checking on a flat tire. Vence said the alleged attackers took Maleah but let him and his 2-year-old son go.

In documents that were filed by Harris County prosecutors, Vence said he "walked with his 2-year-old son and they eventually got a ride from an unknown female" to a hospital, which is when he reported Maleah missing.

The car Vence was driving was later found in Missouri City, Texas, by investigators. Authorities said in the court documents that two dogs "trained to sniff the scent of a cadaver" were drawn to the trunk of the vehicle.

Police also said that surveillance video from the hospital showed Vence was dropped off in that same car. They have not said who was driving.

Surveillance video from a neighbor's home showed that when Vence did leave to go to the airport, his son was the only child with him. A search of the family's home also turned up drops of blood in the hallway that matched DNA taken from Maleah's toothbrush.

Houston Police Chief Art Acevedo said last week that investigators think that Maleah was murdered, and he pleaded with the public to help find her body.

"He's mad as hell," Finner said of the police chief. "All of us are. Everybody. That’s a little baby — and if it’s not Maleah, that's somebody’s child.”