Drug cartels Mexico
Mexican authorities said 15 police officers were killed in an ambush in Jalisco state. Reuters

Suspected drug cartel gunmen have killed 15 police officers in a military-style ambush in the western Mexican state of Jalisco.

Authorities said they believe the policemen were shot dead in retaliation for a series of arrests targeting the Jalisco New Generation cartel.

The Jalisco state police convoy was attacked as it was travelling on a mountainous stretch of a rural road between the Pacific coast resort of Puerto Vallarta and Guadalajara, AP reported.

A burning vehicle was reportedly deployed across the road to block the police convoy which was subsequently surrounded and fired upon.

"They died in a cowardly attack, which means that we can't let our guard down," said Jalisco's state security commissioner Francisco Alejandro Solorio Arechiga, AFP reported.

"The serious thing about this attack was that it was very well planned and orchestrated, with a military-style strategy," said Raul Benitez, a security expert at Mexico's National Autonomous University. "A lot of gunmen were involved. They blocked the highway to surround them [police] and attack with military superiority."

The ambush came days after the arrests of 11 suspected members of the Jalisco New Generation cartel, which has been increasing its influence in the area since being founded in 2010.

Shootouts between security forces and cartel gunmen are common in Mexico since the government declared a war on drugs in 2006 that has seen more than 100,000 people killed or gone missing.

Pre-planned attacks like the one in Jalisco are however rare, as usual fire exchanges erupt when police chases mobsters and not the other way round.