Juan David Ortiz, 35, was arrested on Saturday and charged with four murders and one unlawful restraint with aggravated assault with a deadly weapon. He had kidnapped the woman but she managed to escape before he could take her life.
"He was going to try to commit suicide by cop, he tried to use his phone to make it look like it was a weapon", Garza said.
Besides Ms Luera, police also identified Melissa Ramirez, 29, among the slain.
Alaniz didn't rule out prosecutors pursuing the death penalty for Ortiz, although he said it's too early to tell because the crime is still being investigated and evidence compiled. It is unclear whether Ortiz used his service weapon, or government resources to track victims, Garza said.
The 35-year-old worked for US Border Patrol for nearly 10 years, and went into work as normal throughout the two-week period.More news: Davis Cup roundup: US survives vs. Croatia, France clinches
He joined the Border Patrol shortly after leaving the Navy.
Alaniz said Ortiz has killed four women since September 3, including one transgender woman.
An arrest affidavit states that Ortiz provided officers with details about picking up a woman he identified as Melissa Ramirez on September 3.
Erika Pena approached a state trooper after she said Ortiz pointed a gun at her when she tried to escape from his vehicle, according to the documents. He was captured at 2:30 a.m., when police found him hiding in a hotel parking garage, where he unsuccessfully attempted to draw the gunfire of the arresting officers, Garza said. Webb County District Attorney Isidro Alaniz said Saturday that investigators "consider this to be a serial killer" whose victims were believed to be prostitutes. Like the other victims, Ramirez was shot in the head and left in a road in rural northwest Webb County.
On Thursday, Ortiz picked up another woman - 42-year-old Claudine Ann Luera - and drove her outside of Laredo. She made it to a gas station where she found a state trooper whom she asked for help. According to police, all of the victims had been working in prostitution. The fourth victim, a transgendered female, was found later that day. Two of them were US citizens; the other victims' nationalities are unknown.More news: Hope Fades For Dozens Trapped In Landslides Philippines
Ortiz described a place along a highway where they could find Humberto Ortiz, behind some gravel pits soaked in rain.
Ortiz was believed to have acted alone.
At least two of the victims were USA citizens; the nationalities of the others were not known, Alaniz said.
Webb County Sherriff's spokesperson Eduardo Chapa told CNN that investigators have not ruled out the possibility that Ortiz killed others. Sheriff Martin Cuellar did not return several messages seeking comment.
Border Patrol officials refute those claims, saying Ortiz had a clean background while an agent.More news: Alec Baldwin Confirms His Niece Hailey And Justin Bieber Are Married!
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