Multiple clashes on Thursday between Mexican security forces and alleged criminals left at least 16 people dead in the violence-plagued southern state of Guerrero, the military said.
A first skirmish occurred in the town of Tecpan de Galeana, near the Pacific coast, where two were killed and four more injured.
Later, security forces battled with a criminal group that had attacked a military base in the same area, killing 14 gunmen, according to a statement by the SEDENA national defense secretariat.
Guerrero, one of Mexico's poorest states, has endured years of violence linked to turf wars between cartels fighting for control of drug production and trafficking.
Last year, 1,890 murders were recorded in the state, which is home to the beachside resort city of Acapulco, a former playground of the rich and famous now blighted by crime.
In early October, the mayor of Guerrero's capital city was killed less than a week after taking office, with his grizzly decapitation sparking outrage around the country.
Farther north on Thursday, in Guanajuato state, a car bomb detonated outside a police station, wounding three officers, local officials said.
The blast damaged the police station, four houses and several homes but the police officers were the only people hurt, the department said.
The central region is a thriving industrial hub and home to several popular tourist destinations, but it is also now considered Mexico's most violent state.
On October 4, the bodies of 12 slain police officers were found in different areas of Salamanca, a town in Guanajuato.
Officials say violence in the state stems from a conflict between the local Santa Rosa de Lima gang and the Jalisco New Generation cartel, one of the most powerful in all of Mexico.
"I want to be very emphatic: our priority is the pacification of Guanajuato, and we will achieve this complex task together," state governor Libia Garcia said on social media after Thursday's attack.
She said an air and ground operation had been launched involving state security forces to support the municipal police.
Mexico has suffered more than 450,000 drug-related killings since the government started using the military to fight the cartels in 2006.
President Claudia Sheinbaum, who took office on October 1, has pledged to continue her predecessor's "hugs not bullets" strategy of using social policy to tackle crime at its roots, while also making better use of intelligence.
"The war on drugs will not return," she said, referring to the US-backed offensive launched in 2006.
The northwestern cartel stronghold of Sinaloa has also seen a spike in violence since the July arrest of drug lord Ismael Zambada in the United States.
On Monday, Mexican troops shot dead 19 suspected Sinaloa Cartel members after coming under attack.
Zambada's capture triggered infighting between his supporters and gunmen loyal to imprisoned cartel founder Joaquin "El Chapo" Guzman and his sons.
Zambada accused Joaquin Guzman Lopez, one of El Chapo's sons, of kidnapping him and handing him over to US law enforcement.