Gunmen shot to death four members of a musical group after a performance in the western Mexican state of Michoacan, the state prosecutor's office said Monday.

The men, aged 21 to 37 and part of a local group known as Banda Fugaz, were heading home early Sunday when they were attacked in Puruaran, 185 miles southwest of Mexico City, spokeswoman Magdalena Guzman said.

A fifth man was shot several times, but survived, she said.

Police had not made any arrests and did not identify a possible motive — although Guzman said the band was not known to sing controversial songs about drug trafficking, known as "narcocorridos," which authorities say may have played a role in other recent slayings of Mexican musicians.

On Nov. 25, norteno singer Valentin Elizalde was shot to death along with his manager and driver shortly after performing in Reynosa, across the border from McAllen, Texas. Police are investigating a possible link between the killing and a grisly video posted online set to one of Elizalde's songs, "A Mis Enemigos," or "To My Enemies."

In December, Javier Morales Gomez of the band Los Implacables del Norte was shot to death in a park in the town of Huetamo, Michoacan. Officials have not released a motive in that case, either.

Michoacan has been plagued by gunbattles, killings and beheadings blamed on drug gangs. In early December, federal troops and police launched a large-scale anti-drug offensive.

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