EL PASO, Texas/CIUDAD JUAREZ. Mexico (Reuters) - A U.S. federal court interpreter from El Paso, Texas, has been found murdered in Ciudad Juarez, Mexico's most violent city, U.S. and Mexican authorities said on Friday.

Jorge Dieppa, a U.S. citizen, had worked for seven years as an interpreter at the U.S. District Court in El Paso.

He was kidnapped and murdered in Ciudad Juarez on July 6, the U.S. Consulate in the city said, although his identity was not immediately confirmed.

"Our American Citizens Services unit has contacted his family and is facilitating the transport of his body to the United States," consulate spokeswoman Olga Elena Bashbush said in a statement.

"We extend our condolences to the family and ask the public to respect (their) privacy at this difficult time," she added.

Colleagues at the court said Dieppa, 57, was well-liked, professional and committed to his work.

"We are all, from El Paso to San Antonio, very saddened by what happened to him, it came as a total shock to us," said Tom Hilburger, Dieppa's supervisor and divisional office manager.

A funeral service will be held for Dieppa in El Paso on Saturday.

A spokesman for the Mexican federal prosecutors' office in Ciudad Juarez said police had arrested three suspects in connection with Dieppa's kidnap and murder, while a fourth remained at large.

Arturo Sandoval identified Lizbeth Nayeli Rodriguez, a dancer who met Dieppa in a bar and had a 5-year relationship with him, as the group's alleged ringleader.

After killing Dieppa, Sandoval said the band continued to negotiate a $10,000 ransom with his wife. She declined to pay it and demanded proof Dieppa was still alive, as she did not recognize the caller's voice.

His body was found dumped in a poor neighborhood in the industrial border city. He had been stabbed in the neck, his head wrapped in duct tape and hands and feet bound with electrical cable.

More than 9,000 people have been murdered in Ciudad Juarez since the start of 2008, when a turf war between two rival drug cartels unleashed a wave of criminal mayhem including murders, kidnapping and extortions.

A total of 111 U.S. citizens were killed in Mexico last year amid surging violence, according to the U.S. State Department, which this year extended a travel warning to include 10 states in northern and central Mexico.

(Writing by Tim Gaynor; Editing by Jerry Norton)

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