A Honduran man accused of killing his girlfriend in Louisiana and fleeing to Texas with three of their five children had recently crossed into the U.S. illegally but was released by border authorities on a promise to reappear in immigration court, officials said.

Pedro Alberto Monterroso-Navas, 43, was arrested late Sunday in a trailer park in Katy, Texas; the three children, ages 12, 4 and 2, were found unharmed, officials said.

Monterroso-Navas now awaits extradition to Louisiana on a charge of second-degree murder in the death of Heidi Monroy, also reportedly a Honduran immigrant.

Their two other children, ages 5 and 8, found Monroy's body in a bathtub in the family's apartment in Metairie on Sunday, officials said.

Monterroso-Navas and Monroy, along with their children, had crossed into the U.S. separately within the last two months and had both been part of the recent immigration crush overwhelming border officials in Texas' Rio Grande Valley. 

U.S. Border Patrol agents captured Monroy with three of the children in the valley on May 11, and captured Monterroso-Navas with the two other children on June 26, according to a U.S. Immigration and Customs Enforcement spokeswoman.

All of the family members were released with notices to appear in immigration court after clearing a background check for criminal history and gang affiliations and after providing an address where they planned to stay in the U.S., ICE spokeswoman Gillian M. Christensen told the Los Angeles Times.

That procedure is normal for parents and children who cross the border together -- so that U.S. officials don't break up a family -- and when there aren't enough detention facilities to hold them, Christensen said.

Christensen added that around the time the couple was detained, ICE had only one facility specifically meant for families: a 96-bed site in Berks County, Pa., that is full. Officials on June 27 opened a 672-bed facility for families in Artesia, N.M., she said.

“ICE’s detention capacity nationwide is mostly meant for adults, and when you have families involved, there is a much greater set of requirements -- you’ve got educational requirements, recreational requirements," Christensen said. 

So when families are released instead of taken into detention, Christensen said, “they tell us where their destination is, give us an address, we verify to make sure that actually exists -- a lot of times they’re going to a friend’s house, a relative’s house -- but we don’t vet who they go to."

The family ended up at an apartment complex in Metairie, where they reportedly lived a humble life.

Neighbors told the New Orleans Times-Picayune that the family was apparently living without electricity, with little food, and had been sleeping on a mattress recovered from a dumpster.

Terrlyn Foy, a neighbor who allowed one of the daughters to cook in her apartment, told the newspaper that the family had been living in a spotlessly clean apartment that had nothing in it but the mattress and a television.

Foy, who could not be reached for comment, told the Times-Picayune that Monterroso-Navas had told her that Monroy wanted to leave him and take only the youngest child and that he seemed upset.

The next day, Monroy -- who officials said had checked in with the local ICE office before her immigration court hearing, as she was supposed to -- was found beaten to death. Monterroso-Navas had been scheduled to check in with ICE by Monday, the day after he was arrested.

It was not clear if he had an attorney.

Federal immigration officials told The Times that they had placed an immigration detainer on Monterroso-Navas for when or if he is released from custody.

The five children are with other family members who are in the U.S., Col. John Fortunato of the Jefferson Parish Sheriff's Office said.

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