Mexico adds police as drug killings mount

(Adds police killed in shootout)

TIJUANA, Mexico, Jan 8 (Reuters) - Mexico sent hundreds of police reinforcements to the border city of Tijuana on Tuesday following a rash of organized crime killings and as Mexican media said two cops were shot dead in another northern town.

Some 500 additional officers arrived in the first wave of 1,000 reinforcements, which will more than double the number of federal police already dispatched to Tijuana, located just across the border from San Diego, California.

"It's part of the stepping up of actions against organized crime in this border area," Rommel Moreno, attorney general for Baja California state, told Reuters. "The fight against abductions will continue to be the priority."

Three police officers were abducted and murdered in Tijuana over the New Year. Hundreds of troops were deployed there last month after the attempted murder of a police chief raised suspicions that drug traffickers had infiltrated local police.

Separately on Tuesday, two federal police died in a shootout with with suspected drug gang hitmen in the border city of Reynosa in the northeastern state of Tamaulipas, the dailies Reforma and Excelsior said on their Web sites .

Two witnesses told a Reuters reporter the suspected hitmen attacked a police patrol vehicle in downtown Reynosa and in the ensuing gun battle, a pick-up truck belonging to the gunmen exploded when bullets hit grenades inside.

Much of Mexico's drug violence is centered along the U.S. border where control of smuggling points is crucial.

Northwestern Baja California is Mexico's most violent state with more than 400 gangland-style murders recorded there last year. Over 2,500 people were killed nationwide in 2007 in turf wars between drug cartels.

Mexican President Felipe Calderon has been battling organized crime since he took office a year ago and immediately sent some 25,000 troops and federal police to the country's worst trouble spots. (Additional reporting by Magdiel Hernandez in Nuevo Laredo) (Reporting by Lizbeth Diaz; Writing by Catherine Bremer, Editing by Jackie Frank)