At least 15 police officers were killed in an ambush by a gang in western Mexico, an official said Tuesday, one day after another attack against authorities in Jalisco state.

At least 15 police officers were killed in an ambush by a gang in western Mexico, an official said Tuesday, one day after another attack against authorities in Jalisco state.

Five other officers were wounded in the assault, which took place on Monday afternoon on a highway near the village of Soyatan as a convoy carrying an elite police unit headed to Guadalajara, Mexico's second biggest city.

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

"Fifteen of our colleagues lost their lives. Five officers were also wounded in this regrettable event, they're all in stable condition," he said.

The Jalisco state prosecutor's office had reported the attack late Monday but had not confirmed the fatalities, saying only that several officers had been "hit by bullets."

Authorities say the assault appeared to be in revenge over the arrest of gang suspects in an investigation into a failed assassination attempt against Solorio on March 30.

"These attacks are a reaction of organized crime after the attack against me," Solorio said after a meeting of federal police, military and state security officials in Guadalajara.

Authorities did not identify the gang but a security source told AFP that they suspect the powerful Jalisco New General Drug Cartel carried out the assault.

In a previous deadly ambush, gunmen opened fire on federal police in the town of Ocotlan on March 19, leaving 11 people dead, including five officers, three suspects and three bystanders.