Louisiana Man Accused of Murdering Woman, Abducting 2 Daughters & Killing 1 In 'Heinous' Crime: Sheriff

"These are unspeakable crimes," said authorities, who suspect human trafficking after cages were found in the neighborhood where the surviving girl and her sister's body were found.

A Louisiana man was arrested in Jackson, Mississippi after allegedly murdering a mother of two young girls -- who he's accused of then abducting, before killing one of the children.

On Thursday, the Tangipahoa Parish Sheriff's Office announced 36-year-old Daniel Callihan was located and taken into custody, accusing him of the murders of 35-year-old Callie Burnett and her 4-year-old daughter Erin. Authorities referred to his alleged actions as "brutal and heinous acts of violence" in a press release.

"Our hearts are with all those affected by this tragic event. These are unspeakable crimes," said Sheriff Daniel Edwards in a statement. "We ask everyone to keep Callie's family in your prayers."

Callihan and Burnett dated "off and on," according to investigators.

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The search for Burnett's two daughters, aged 4 and 6, began earlier in the day, when an Amber Alert was issued for the pair after their mother was found dead inside her home. According to WDSU , Burnett's father had last seen her on Tuesday evening, but couldn't get in contact with her the next day and saw her car was missing. He reported her missing to the sheriff's office on Wednesday evening, before he entered her trailer on Thursday morning and found her body covered in blood.

The Amber Alert said Callihan was wanted "for questioning for a domestic violence incident, which occurred at the time of the abduction and resulted in a homicide." Following the alert, Burnett's car -- which Callihan had apparently stolen -- was spotted in Mississippi.

Police in Jackson, MS were notified about a suspicious person in the area, before a brief chase led to Callihan's arrest.

"He had the victim's car along with her alive-and-well 6-year-old child," said office Chief Deputy Jimmy Travis . The body of Erin, meanwhile, was found unburied in the woods nearby.

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Jackson police Chief Joseph Wade told reporters that, based on items found at the crime scene, "this may be the place where there has been some human trafficking done."

"We see cages, small animal cages. This is very, very disturbing to me as a police chief and as a father to witness and see what I saw," he added, saying he also contacted The Mississippi Bureau of Investigation's human trafficking division for assistance on the case -- which was then turned over to the FBI.

"This was a horrible, horribly tragic situation that was committed by the actions of a coward," said Wade.

As of Thursday evening, Callihan still hadn't been questioned. The 6-year-old, meanwhile, was taken to the hospital for treatment.

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