Thirteen people have been killed and six others gravely wounded following numerous shootouts in the Mexican state of Jalisco, officials said.
Bullet riddled vehicles and buildings showed the amount of firepower used by unnamed assailants who battled with
police on Sunday.
Police information points to two groups who may be responsible for the violence, the Templar Gentlemen and the
New Generation Cartel of Jalisco.
In total, more than 60,000 people have died in drug-related violence and more than 5,000 disappeared in Mexico since December 2006.
Drug war fallout
In the latest fallout of the drug war, Luis Cardenas Palomino, one of the most senior Mexican federal police officials, has announced that he is resigning on December 31.
Live Box 201210961244305159
Cardenas Palomino faces no charges of wrongdoing, but under his watch there was a shoot-out in June between police in the Mexico City airport that killed three officers, and an attack by federal police in August on a US diplomatic vehicle that wounded two US agents.
In June, federal police smuggling drugs from Peru killed three agents who attempted to arrest them at the Mexico City international airport. Cardenas Palomino eventually replaced all 348 officers responsible for airport security.
In August, federal police opened fire on on what turned out to be a car with diplomatic plates. The attorney general's office has charged 14 federal police officers with attempted murder, while five police commanders have been accused of lying in the case.
The federal police is being reorganised as part of a major security overhaul by Mexico's new president, Enrique Pena Nieto.
Mexico's congress passed a law last week that closed the ministry of Public Security, a pillar in the fight against drugs under former president Felipe Calderon.
The federal police will now be under the control of the ministry of interior.