A Texas appeals court on Tuesday halted the execution of a man who has spent more than 30 years on death row and had been set to die by lethal injection this week over the killings of six girls and young women found buried in the desert near El Paso.

State prosecutors withheld evidence favorable to Brittany Marlow Holberg during her 1998 murder trial that resulted in her being sentenced to death, a federal appellate court panel ruled Friday.

The federal appeals court said the prosecution failed to disclose that a key trial witness was a paid informant.