Mexican authorities say this week's gun battle at the Gulf of California resort of Puerto Penasco started inside a luxury beach condo complex and involved two government helicopter gunships that opened fire during the confrontation.

Mexico's federal police say that two government Blackhawk helicopters opened fire on at least 10 vehicles as they tried to flee with top Sinaloa drug cartel lieutenant Gonzalo Inzunza. The vehicles were hit by gunfire in the Wednesday battle.

Inzunza apparently owned or rented a beachside villa at the complex, which officials did not name.

Federal police said late Thursday that an analysis of blood stains found in the vehicles show that Inzunza was among those killed or wounded, though his body hasn't been found.