The top cop in this violent border city accused Mexican federal police of firing on his convoy as he was headed to the municipal jail to quell a brawl that left 17 inmates dead.

Julian Leyzaola, who was unhurt in the incident, told a press conference that at least 20 "fully identified" federal police officers shot at vehicles carrying him and his bodyguards.

The incident took place in the wee hours of Tuesday as the chief was traveling to the municipal lockup in Ciudad Juarez, a gritty metropolis just across the border from El Paso, Texas.

City clerk Hector Arcelus dismissed the federal cops' claim that the shooting was the result of confusion.

The federal officers are "perfectly" familiar with the vehicles used by Leyzaola and his escorts, according to Arcelus, who said it was "neither logical nor credible that they (the feds) acted randomly."

The Juarez city administration will file a criminal complaint against the federal government, the clerk said.

Municipal authorities also demanded that the federal officers involved in the shooting be turned over to prosecutors.

Tuesday's episode comes after the killing by federal police of a member of Mayor Hector Murguia's security detail at a checkpoint in Juarez.

At the time, the mayor demanded that the officer who "artfully shot" his bodyguard be charged with homicide and Murguia later got into a shouting match with federal cops who pointed their assault rifles at him during a chance encounter in the city.

Murguia has announced a gradual withdrawal of the more than 5,000 federal police patrolling Juarez, to begin in September.

The border city of roughly 1.5 million people in Mexico's murder capital, with more than 8,500 homicides since the beginning of 2008.

The carnage is blamed on a turf war between the Juarez and Sinaloa drug cartels, both of which rely heavily on local street gangs to carry out attacks.

The deployment of nearly 10,000 soldiers and federal police - the troops have already gone - in Ciudad Juarez did nothing to reduce the level of violence.