TIJUANA, Mexico (Reuters) - Drug hitmen have killed a popular Mexican singer along with his manager and assistant near the U.S. border, authorities said on Wednesday, the latest murder among musicians who sing “narcocorrido” ballads glorifying drug traffickers.

The body of Jesus Rey David Alfaro, known as “The Little Rooster,” was one of six that turned up tortured, murdered and pinned with threatening messages for Mexico’s army last week in the border town of Tijuana near San Diego.

“We believe Alfaro had links to the Arellano Felix cartel,” said an official with the Baja California state attorney general’s office who declined to be named.

The official was referring to Tijuana’s main drug smuggling cartel, which is fighting a gory turf war with traffickers from Mexico’s Pacific state of Sinaloa, led by the country’s most-wanted man, Joaquin “Shorty” Guzman.

At least half a dozen Mexican folk singers, who play narcocorridos and upbeat, brassy “grupera” music, have been killed since Mexico’s drug war flared in 2006.

Alfaro, a regular act at Tijuana’s biggest bars and music halls, was found covered in a blanket in wasteland on the edge of the city with rope marks around his neck, suggesting he was tortured before he was shot in the head, the attorney general’s office said.

Drug hitmen pinned a message on his body saying “You’ll be next,” a taunt aimed at the thousands of soldiers sent by President Felipe Calderon to Tijuana to crush the drug gangs and clean up police forces working with the cartels.

Tijuana, long a transit point for narcotics heading to the United States, has seen a spike in murders this past year, with drug gangs even killing children. More than 2,500 people were killed in drug violence in Mexico last year and at least 320 people have died so far this year.