Eleven killed in Mexico gun battle

CULIACAN: Seven police officers and four gunmen were killed Monday in a shootout in Mexico's northwestern state of Sinaloa, a stronghold of one of the country's ruthless drug gangs, officials said.

The state police officers were ambushed, but returned fire "and managed to kill four of the aggressors," an official with the Sinaloa state attorney general's office said.

Two agents were also wounded in the shootout, which took place near a tourist site known as El Fuerte, said the official, speaking on condition of anonymity.

Security forces launched a search for the assailants after the clash, with a police helicopter joining the hunt, the official said.

Sinaloa state is the stronghold of Joaquin "El Chapo" ("Shorty") Guzman, who the US Treasury Department considers "the world's most powerful drug trafficker." Forbes magazine estimates his wealth at $1 billion.

More than 50,000 people have been killed and 5,000 have gone missing in Mexico since outgoing President Felipe Calderon launched a military crackdown on the cartels when he took office in late 2006.