The FBI suspects that Esteban Manzanares, a Border Patrol agent who was found dead inside his south Texas home, is responsible for the kidnapping and assault of a woman and two teenage girls in the United States illegally, the agency said on Thursday.

The U.S. Customs and Border Protection said agents encountered an injured woman during their regular operations Wednesday night near McAllen, which is close to the Texas-Mexico border about 350 miles from Houston. The woman told agents that she and the two others had been attacked by a man, which prompted authorities to start a "search and recovery" operation. Border agents later found a second injured female.

Both the Border Patrol and the FBI said that the investigation led authorities early Thursday to agent's home in Mission, a suburb of McAllen. The agent was found dead inside. Law enforcement officials discovered the third female in the agent's apartment, the border patrol said. The victims are receiving medical treatment.

The Monitor newspaper in south Texas is reporting that the immigrants are from Honduras, and that they include a 32-year-old woman and her 14-year-old daughter. It's unclear how the second teenager may be related. 

A Border Patrol spokesman at the Rio Grande Valley Sector, Danny Tirado, said Manzanares had been with the agency since 2008. Tirado did not elaborate on the circumstances of the kidnapping.

"We believe he is the person responsible for the kidnappings and the assault of all three of them," said Michelle Lee, an FBI spokeswoman in San Antonio. She did not elaborate on the investigation.

A CBP official told the Associated Press that the agent was on duty when he encountered the females and that his shift had ended by the time authorities showed up at his house and he shot himself. The official spoke on condition of anonymity because it is an ongoing investigation by the FBI.

Manzanares had an ex-wife, Susana – their divorce was finalized on Jan. 29 – with whom he had a 6-year-old son, and a 1-year-old daughter. Susana told the Monitor that an FBI agent told her that Manzanares had committed suicide. “I didn’t know anything, just that he killed himself,” she told the paper. “That’s the only thing that they told me.”

Manzanares' step-sister, Joanna Manzanares, said her brother was a "great person, a helpful and amazing person."

Sgt. Manny Casas, a spokesman for the police department in Mission, said his agency got a call from the FBI at 12:39 a.m. Thursday to assist with "a kidnapping situation" at an apartment complex.

The police department's SWAT unit was called in after officials reported shots being fired from an apartment at the complex. Casas said he did not know if the SWAT team entered the home and had no other details about who was found in the apartment.

Lee said the FBI was awaiting an autopsy report before releasing more information about how the agent died.

Customs and Border Protection spokeswoman Jenny Burke said the agency "takes this incident extremely seriously and (is) fully cooperating with the investigation."

Based on reporting by the Associated Press.

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