HOUSTON -- Texas authorities have charged a U.S. Border Patrol supervisor with murdering four female sex workers during a two-week killing spree that ended when a fifth woman escaped from him and found help.

Juan David Ortiz was arrested Saturday after he was found hiding in a truck in a hotel parking lot in Laredo.

Webb County District Attorney Isidro Alaniz said he was charged with four counts of murder as well as aggravated assault and unlawful restraint. 

The victims, including a transgender woman, had been murdered since Sept. 3. Alaniz says authorities consider Ortiz a serial killer. The names of the victims were not released but Alaniz says two are U.S. citizens. Nationalities of the others are not yet known.

Ortiz was being held Sunday on four murder counts, plus aggravated assault with a deadly weapon and unlawful restraint. His bond is set at $2.5 million.

The Navy said Ortiz was in the service for almost eight years. A biography of Ortiz released Monday said that he enlisted in the Navy in July 2001 and served until May 2009. He was listed as a hospital corpsman, second class.

He joined the Border Patrol shortly after leaving the Navy. The Border Patrol often recruits servicemembers and gives hiring preference to eligible veterans.

Congressman Henry Cuellar (TX-28) released the following statement following the arrest:

"The arrest of the border patrol agent who has allegedly committed multiple murders could not have happened without the hard work and expertise of the Texas Rangers, the Webb County Sheriff's Office, the Webb County District Attorney's Office, and Laredo Police Department. 

Having just spoken with Webb County Sheriff Martin Cuellar, there is no doubt in my mind that the heroic efforts of these four agencies have saved lives; they are to be commended. Establishing and maintaining high standards for Border Patrol agents is a top priority for my office. We have advocated for and implemented new standards during the hiring process as well as new standards of professionalism after joining Border Patrol.

Just this afternoon I spoke with CBP Commissioner Kevin McAleenan to talk about the situation in Laredo. We have agreed to work together on the hiring and professionalism of border patrol agents. We spoke about how more steps need to be taken to make certain that people who want to become Border Patrol agents receive the appropriate psychological screening to ensure that no person who is capable of these type of actions is allowed to join or remain in the ranks. We also spoke about hiring more Professional Responsibility officers so that they can police their own. 

The commissioner assured me that we will continue to work together to address these issues. I also intend to speak with the General Inspector of DHS who is working on this matter, to express my concern that this is the second case this year involving a border patrol agent who has killed someone in Laredo. I also intend to talk to the VA about the particular facts of this Border Patrol agent who was a veteran. 

As a member of the House Appropriations subcommittee for Homeland Security, I will be asking my colleagues to help me secure additional resources to address the above issues.

Border Patrol agents are great men and women who work hard to keep us safe, and we thank them for their work. However, this is the second instance this year involving a Border Patrol agent killing someone in Laredo. We will continue to monitor this situation to see how we can provide any additional resources to DHS.

I extend my condolences to the families of the victims during this difficult time.”