Cartel violence in the Mexican border state of Chihuahua left three police officers murdered in separate attacks this week. Several officers were also wounded.

The first deadly attack occurred on Tuesday morning in the state capital’s colonia Cerro Prieto as state police assigned to the Comisión Estatal de Seguridad (CES) traveled in a marked vehicle. The officers were preparing to conduct an arrest of several street-level drug suppliers believed to belong to “Los Sureños” gang. Officers came under intense gunfire from passengers in several vehicles. They returned fire and repelled the attack, wounding at least one gunman and taking three into custody. One officer identified as Sinuhé Domínguez Maldonado was mortally wounded and died at a local hospital, according to the Chihuahua State Police Director Óscar Aparicio Avendaño.

The second attack also occurred on Tuesday in Bocoyna located approximately 150 miles west of the state capital. The Bocoyna chief of police was traveling in an official vehicle when he came under intense rifle fire. Police repelled the attack, but Chief Alejandro Marcie González, 35, died at the scene, and a second officer sustained non-life threatening wounds, according to local reports.

A third Tuesday attack targeted two municipal police officers sitting in a vehicle in Ciudad Juarez. The officers sustained non-life-threatening wounds, according to local reports.

The final attack focused on three off-duty Chihuahua state policemen traveling in a personal vehicle. It is believed that at least one of the attackers was wounded but able to flee. During the exchange, one female officer died. Investigators are conducting searches of local clinics and hospitals for the wounded shooters.

Robert Arce is a retired Phoenix Police detective with extensive experience working Mexican organized crime and street gangs. Arce completed work assignments in the Balkans, Iraq, Haiti, and recently completed a three-year tour in Monterrey, Mexico, for the U.S. Department of State, International Narcotics and Law Enforcement Program.