Mexican officials say gunmen have killed a small-town mayor and three other people in a drug-plagued northern state.

Durango state prosecutors' spokeswoman Ivonne Rodriguez says assailants opened fire on Mayor Luis Carlos Ramirez as he was talking to a mechanic at his home in Ocampo.

The mechanic was also killed in Monday night's attack, along with two others. A motive has not been determined.

Rodriguez says Ramirez survived a similar attack in November, but declined to comment further.

Two journalists have been shot dead in Durango in the last month.

More than 10,750 people have been killed in drug violence since President Felipe Calderon launched a crackdown on cartels in 2006.