(changes dateline, re-ledes with killings in Guerrero)
Six people, including a police officer, were killed in separate incidents in the southern Mexican state of Guerrero, authorities said Friday.
The policeman died Thursday night when several assailants opened fire on a patrol car in the Pacific resort city of Acapulco, the state Public Safety Office said.
Two cops were wounded in the attack.
The bodies of an unidentified man and woman were found early Friday, also in Acapulco, sources in the Guerrero state Attorney General's Office told Efe.
The other three fatalities were in El Paraiso, a village in the coastal municipality of Atoyac de Alvarez, where three local farmers were found shot to death.
Authorities suggested that one or more of the incidents could have been linked to conflict among rival criminal gangs.
Several of Mexico's powerful drug cartels have been battling to control Guerrero's Pacific coastline, a key smuggling corridor.
In the northern city of Torreon, meanwhile, three members of an elite state police force and a civilian were killed and another officer was seriously wounded in an attack by suspected drug cartel hit men.
The security spokesman in Coahuila state, Sergio Sisbeles, told Efe the incident occurred around 11:30 a.m. Thursday when the four state law-enforcement officers were on patrol.
He said the attack was an act of revenge by organized crime elements after two suspected cartel enforcers were arrested Wednesday and turned over to federal prosecutors.
One unidentified male passerby was also killed in the attack.
Comarca Lagunera, a metropolitan area straddling parts of the northern states of Durango and Coahuila where the attack occurred, has seen an uptick in violence in recent years stemming from a turf war between the Sinaloa and Los Zetas cartels, Mexico's two most powerful drug mobs.
Organized criminals have carried out massacres, shootings at bars and even bomb attacks on media outlets in that metro area.
Conflict among rival cartels and between criminals and the security forces has claimed more than 50,000 lives in Mexico since December 2006, when newly inaugurated President Felipe Calderon - whose term ends in December - militarized the struggle against drug trafficking. EFE