MEXICO CITY – Five people, four of them police, were killed in the northern border state of Chihuahua and three others were found dead inside a car in neighboring Sonora state, Mexican authorities said on Thursday.

Two Chihuahua state detectives were fatally shot after midnight Wednesday while riding in their patrol car on the south side of Ciudad Juarez, a gritty metropolis just across the Rio Grande from El Paso, Texas.

Elsewhere in Juarez – Mexico’s murder capital – two police were killed as they filled up their vehicle at a gas station. Two other officers and two station employees were wounded in the shooting, and one of the civilians later died while receiving first aid.

A municipal policeman was listed in critical condition after he was shot outside his home in Ciudad Juarez.

Sonora state police found the bodies of three people inside a parked car in Nogales, which lies opposite the town of the same name in Arizona.

The victims were beaten and then strangled to death, authorities said, adding that one of the men was an army veteran, while another had once been arrested on suspicion of murder.

The car, which had Arizona license plates, was left with its engine running. Police found one body in the back seat and the other two in the trunk.

Mexico has been plagued in recent years by drug-related violence, with powerful cartels battling each other and the security forces in a scramble for smuggling and distribution routes.

The many-sided conflict is blamed for around 15,000 deaths in the past three years and the 2009 toll stands at roughly 6,500. EFE