Two Mexican Police Chiefs Killed

Two police chiefs were shot and killed within hours of each other in a violence-plagued region near the United States where drug smugglers have been battling for control of key routes across the border.

It wasn't immediately clear if the killings Monday were related, but authorities say violence has spiked in Mexico's northeast since the 2003 arrest of the area's top reputed drug dealer set off the turf war.

Hector Ayala, chief of police in the wealthy town of San Pedro Garza Garcia outside Monterrey, was killed Monday when a car overtook his vehicle and opened fire.

Four hours earlier, Sabinas Hidalgo police chief Javier Garcia was abducted by armed assailants, bound and shot in the back of the head. His body was found alongside a highway outside the farming town of 30,000, about 50 miles north of Monterrey and 80 miles south of the U.S. border at Laredo, Texas.

Garcia had taken over as Sabinas Hidalgo's police chief last month.

Nuevo Leon state prosecutor Luis Trevino said investigators had made no arrests and were still trying to determine a motive for the killings. He said neither police chief had reported receiving threats.

"We have to base our investigation on reality and at this point we cannot say whether either attack is linked to organized crime," Trevino told reporters.

Violence in the area has been on the rise since March 2003, when reputed drug lord Osiel Cardenas was arrested during a shootout in Matamoros, across the border from Brownsville, Texas. Another accused drug lord, Joaquin "El Chapo" Guzman, has been fighting smugglers loyal to Cardenas to gain access to drug smuggling routes in Nuevo Laredo and other border cities.

In June, Alejandro Dominguez died in a hail of gunfire just eight hours after taking over as police chief of Nuevo Laredo, a city across from Laredo that has been crippled by a wave of drug-related violence.