MEXICO CITY — At least 14 police officers were killed in an ambush in the western Mexican state of Michoacan on Monday, a reflection of the intensifying violence between security forces and criminal groups in one of the country’s most volatile regions.

The state police squadron had been ordered by a court to enter the municipality of Aguililla, where drug cartels have long held significant influence, to retrieve a woman and her daughter. Four patrol cars were ambushed on a main road just outside the city.

“Several armed civilians fired on them,” the state security department said. Two of the patrol cars were set on fire.

Mexican President Andrés Manuel López Obrador ran for office on promises to address the root causes of organized crime, a strategy he has called “abrazos, no balazos” — hugs, not bullets. Still, he pushed for the creation of a national guard, aimed at strengthening security in cities with weak local police.

Monday’s attack cast more doubt on the effectiveness of his approach. There were 2,966 homicides in Mexico in August, the most ever recorded for that month. The national guard now has 70,000 members, but many have been dispatched to Mexico’s southern and northern borders to deter migration to the United States, part of a bilateral plan with the Trump administration.

On Monday, before news of the attack was reported, López Obrador planned to devote his morning news conference to the topic of security, touting his plan.

“We are doing it in a professional way,” he said. “It is a new strategy where the fundamental thing is to improve the living and working conditions of the people, never again to disregard the Mexicans.”

Alfonso Durazo, the country’s secretary of public security, said Monday that López Obrador had inherited a “chronic crisis of insecurity” from previous administrations. But the attack on police in Michoacan suggests that violence — particularly between criminal groups and the government — is deepening. The number of security personnel killed Monday was the most in a single incident in recent years.

Michoacan state police were instructed by a local family court Monday to take a woman and her daughter from Aguililla to Morelia, the state capital, as part of a judicial order, Michoacan Gov. Silvano Aureoles said at a news conference. Authorities said they were still looking into the details of what Aureoles called the “cowardly” ambush.

The government’s public security secretariat tweeted that it “condemns the attack in which 14 police officers died in Aguililla, Michoacán. We are in communication and we will make available to the state government all of our human and technological resources to find the aggressors and bring them to justice.”

Authorities did not confirm any arrests. In Mexico, the majority of homicides go unsolved.

State police have been dispatched to several cities in Michoacan where local police have failed to stand up to criminal organizations. In some places, local police are accused of collaborating with organized-crime groups. As of last month, four state police officers had been killed on duty in 2019. But many more have come under attack.

Across Mexico, 421 officers were killed in 2018, according to the research organization Causa en Común. So far in 2019, 308 have been killed. By comparison, 47 police officers in the United States were shot to death while on duty in 2018, according to the National Law Enforcement Officers Memorial Fund. The U.S. population is 2½ times bigger than that of Mexico.

In August, police in Michoacan discovered 19 bodies in the town of Uruapan. Nine were hung from a bridge along with signs with written threats. 

The Jalisco New Generation Cartel, which has gained ground across Mexico, has been outspoken about its intention to take control of parts of Michoacan. In one video, released in September, men claiming to be leaders of the cartel address residents of another of the state’s towns, Tepalcatepec.

 “This fight is not against the citizens of Tepalcatepec, but it is with El Abuelo and his cartel,” one masked man says in the video, referring to a rival. “If you want this war to end, take El Abuelo and his cartel out of Tepalcatepec.”