The deputy police chief of Magdalena, a city in the western Mexican state of Jalisco, was killed by gunmen, prosecutors said.

Victor Manuel Hernandez Sotelo was murdered Monday by two subjects on a motorcycle who rode up to his SUV and opened fire with 9 mm weapons in Guadalajara, the capital of Jalisco.

The police chief's SUV crashed into a public bus after the shooting and the gunmen escaped, the Jalisco Attorney General's Office said.

Hernandez Sotelo was shot twice in the head and died instantly, investigators said.

The police chief had driven to Guadalajara for a doctor's appointment.

Investigators are trying to determine the motive for the killing and whether the police chief had received death threats, the AG's office said.

About 50,000 people have died in Mexico's drug war since December 2006, when President Felipe Calderon declared war on the country's powerful cartels, sending soldiers into the streets to fight criminals. EFE