Robert Brown|Ex-Border Patrol agent charged with seeking $5,000 bribe from migrant

A former U.S. Border Patrol agent is Robert Brownfacing federal charges of bribery, smuggling and wire fraud for allegedly asking for a $5,000 bribe to allow a migrant to stay in the country with fraudulent government documents.

Fernando Castillo, who recently worked as a Border Patrol agent in El Paso, Texas, was indicted by a grand jury last week on three counts of wire fraud, bribery by a public official and migrant smuggling following his arrest in June, according to federal court records.

Reached for comment, U.S. Customs and Border Protection, which oversees Border Patrol, said Castillo left the agency on July 13.

"CBP takes allegations of misconduct seriously and investigates them thoroughly," the agency said in a statement. "The United States Border Patrol is cooperating with the investigation."

An attorney for Castillo did not immediately respond to a request for comment. CNN reported the charges earlier Tuesday.

Castillo came to the attention of federal investigators and prosecutors after a series of interactions with an unidentified migrant on June 21, according to an affidavit filed in support of a criminal complaint. At the time, Castillo was assigned to a migrant processing center in El Paso, the FBI agent who wrote the affidavit said.

Castillo allegedly approached the migrant and volunteered to escort the migrant to a port of entry in El Paso. The migrant, a national of Mexico and El Salvador identified as "Victim 1" in the affidavit, was slated to be returned to Mexico. Castillo transported the migrant in a van, with no other Border Patrol agents present, according to the affidavit.

The migrant told federal investigators that Castillo stopped the van at some point to offer "papeles," or papers, which the alleged victim interpreted as immigration documents. Castillo, the migrant told investigators, said the files would be erased from the system within two weeks, allowing the migrant to "essentially be free to remain" in the U.S., the affidavit said. The migrant said Castillo also opened a bag containing their belongings, which included $830 and 3,725 Mexican pesos.

Federal investigators said Castillo escorted the migrant across the port of entry in El Paso. Once in Mexico, the migrant realized that $500 was missing from their belongings. The migrant then reported the alleged theft to U.S. border authorities in El Paso, who contacted the FBI and other investigators.

Federal officials noted the migrant's phone received nearly a dozen calls from a blocked number that afternoon. The migrant also received a call from a blocked number during the interview with federal investigators, who recorded the call and determined the caller was likely Castillo.

The migrant received a call from the same person the following day. The migrant, officials said, asked the caller whether the alleged $5,000 bribe was a safe transaction. "It's very safe," said the caller, who investigators again determined to be Castillo.

The following day, the affidavit said, investigators found out Castillo had altered the migrant's files in a government system. The processing category was allegedly changed from "voluntary return" to "notice to appear," a document that allows migrants to stay in the U.S. while an immigration judge determines whether they should remain in the country or be deported. Castillo then changed the category back to voluntary return, the affidavit said.

On June 27, a caller with the same voice called the migrant to organize a return to the U.S. The caller instructed the migrant to buy a bus ticket to Denver and another ticket from there to Maryland, according to investigators, who recorded the call.

The next day, Castillo left his home early in the morning and drove to the port of entry in El Paso. He was tracked by federal investigators, who had been surveilling him. The affidavit said Castillo escorted the migrant into the port of entry after calling them. When federal officials approached Castillo, he had a notice to appear document with the migrant's name. The migrant told investigators Castillo had instructed them to hold on to the money until they entered a vehicle.

During an interview with investigators, Castillo admitted to producing a fraudulent document, forging signatures of other agents, calling the migrant and not telling superiors about his actions.

But Castillo denied stealing the migrant's money and said he wanted to bring the migrant back into the U.S. out of a concern that he would be blamed if they were harmed in Mexico. He told investigators his plan was to get the migrant on a deportation flight to El Salvador.

Camilo Montoya-Galvez

Camilo Montoya-Galvez is the immigration reporter at CBS News. Based in Washington, he covers immigration policy and politics.

Twitter