Prosecutors in the Mexican state of Chihuahua say they found the bullet-riddled bodies of six members of the same family in a mountainous area.

No motive was given for the killing, but drug trafficking, illegal logging and drug cultivation are all common in the northern region.

State prosecutors' spokesman Eduardo Esparza says the victims are men between the ages of 45 and 55, and all from the same family.

He said the bodies were found late Friday near a dirt road.

Chihuahua state police said Saturday that two army battalions posted in the border city of Ciudad Juarez to fight drug-fueled violence would be rotated out, with fresh troops replacing them. The statement said such 60-day rotations are routine.