A transgender woman from Laredo, Texas, was one of the victims in what law enforcement officials are calling a “killing spree” in which a U.S. Border Patrol agent is the suspect.

The body of Nikki Enriquez, 28, was found Saturday near Interstate 35 in south Texas, USA Today reports. She died of a gunshot to the head, sustained Friday or early Saturday, according to the paper. News accounts initially misgendered and deadnamed her, but as of Tuesday activists confirmed she was a transgender woman.

She is one of four women Juan David Ortiz, 35, is charged with murdering, reports the Caller-Times of Corpus Christi, Texas. He is an intelligence supervisor for the Border Patrol, and authorities say he deliberately selected sex workers as his victims.

He was apprehended early Saturday after a woman escaped from him the night before, Webb County-Zapata County District Attorney Isidro Alaniz told The Texas Tribune. “He picked [the woman] up, she went willingly with him, and then while she was with him things started to get dangerous for her and when she tried to escape from him at a gas station that’s when she ran into a trooper,” Alaniz said. “In our opinion, he is the sole person responsible for this horrific serial killing spree.”

Documents from the district attorney’s office identified the woman as Erika Pena, the Tribune reports. Ortiz “began to act weird when she began to speak about Melissa, a female she knew who had been discovered dead the week before,” a criminal complaint states. She then managed to free herself when they stopped at a gas station about 9 p.m. Friday.

Police tracked down Ortiz at a Laredo-area hotel garage about 2:30 a.m. Saturday, CNN reports. “He gave a verbal confession to killing four women between September 3 and early Saturday,” according to CNN.

Authorities said Ortiz specifically chose sex workers as his victims. He knew all his victims, and he selected them because they were vulnerable and because of “the dislike that he had for this community of people,” Federico Garza of the Webb County Sheriff's Office told CNN, adding, “At one point, Ortiz was able to gain their trust and viciously shot them.”

Besides Enriquez, the victims include Melissa Ramirez, 29, Claudine Luera, 42, according to CNN. Another has been identified, but authorities won’t release her name until they’ve contacted her family. Police and prosecutors haven’t ruled out the possibility that more women were killed in the spree.

Enriquez, who also went by the name Janelle, was remembered by her family as an enthusiastic, affectionate person. She “was very outgoing. Always smiling,” a cousin, Veronica Castillo, told the Laredo Morning Times, adding that Enriquez “was loved by the gay community.”

Enriquez is the 21st transgender American reported murdered this year. Most of them have been women of color.

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