A police convoy in Mexico's Michoacan state were ambushed on Monday by gunmen who killed at least 13 officers and wounded nine.The attack appears to be the work of the Jalisco New Generation cartel, which is one of Mexico's most powerful criminal groups and one of several fighting for influence in Michoacan.Visit Business Insider's homepage for more stories.MORELIA, Mexico (AP)State police expected the worst when they ventured into the wild township of Aguililla to serve a single warrant. Commanders sent 42 officers in five trucks.It wasn't enough. More than 30 suspected drug cartel gunmen were waiting for them Monday, some in vehicles that were apparently armored, prosecutors in Mexico's western state of Michoacan said.Officials said the gunmen opened up on the police convoy with .50-caliber sniper rifles and AR-15 and AK-47 assault rifles at about 8:00 a.m. Recordings circulating on social media show police calling for backup."We're under attack! We're under attack! There are wounded! There are wounded!" one officer says amid cries from another officer who was hit and with sound of gunfire in the background, according to Mexico News Daily.Thirteen officers were killed, some of their bodies still inside the patrol trucks when the vehicles were set afire. Nine other officers were wounded.The attackthe worst on Mexican law enforcement in yearscame in a state where violence blamed on drug gangs has jumped in recent months.Authorities said the state police convoy was ambushed as it sought to enforce a judicial order at a home in El Aguaje, a town in the municipality of Aguililla, which is the reputed birthplace of Nemesio "Mencho" Oseguera, leader of the hyper-violent Jalisco New Generation cartel.The police convoy was going to pick up a woman and her daughter to testify as victims of domestic violence, according to Israel Patron, the Michoacan state director of public security.Patron said federal and state forces, including Mexico's new National Guard, are conducting a manhunt for the attackers."No attack on the police will go unpunished, and this was a cowardly, devious attack because they laid an ambush in this area of the road," Gov. Silvano Aureoles said.Images published in Mexican media showed vehicles burning in the middle of a highway and messages apparently signed by Jalisco New Generation, one of Mexico's most powerful and rising cartels. Aureoles said their authenticity was under investigation.Banners signed by the group, also called CJNG, indicated that the attack was directed at supporters of rival gangs.Later in the day, an Associated Press journalist saw two gutted patrol cars at the entrance to El Aguaje surrounded by hundreds of bullet casings. Two police trucks were towed away.Streets were nearly empty as people apparently decided to stay indoors after the violent events.After the attack, the area in western Mexico's so-called hot lands was reinforced by federal and state security forces, which set up checkpoints to hunt for the assailants.Michoacan, an important avocado-growing state, has recently has seen a spike in violence that has brought back memories of the bloodiest days of Mexico's war on drug cartels between 2006 and 2012.In August, police found 19 bodies in the town of Uruapan, including nine hung from a bridge. Later, an area roughly 45 miles north of Aguililla was the scene of fierce clashes between members of Jalisco New Generation and regional self-defense groups.In 2013, civilian groups faced with what they said was state inaction armed themselves in Michoacan to fight the Knights Templar cartel, one of whose bases was Aguililla.They said they took up arms to defend themselves from kidnappings, extortion and killings by cartels. But some of the self-defense or vigilante groups later became infiltrated by cartels and gangs.The government of former President Enrique Pea Nieto launched a process to disarm and legalize the vigilante groups and incorporate them into official security forces.Aureoles, the governor, says the self-defense groups haven't returned and has criticized federal authorities for not attacking drug cartels in Michoacan with sufficient force and for negotiating with vigilante groups he refers to as criminals.Besides avocado orchards, Michoacan for decades has been known for marijuana plantations and the making of methamphetamine. It is home to the port of Lzaro Crdenas, a key entry point for precursor chemicals used to make synthetic drugs.Mexico's current president, Andres Manuel Lopez Obrador, has argued the best way to fight organized crime is by eliminating corruption and attacking the root causes of poverty.He has advocated a "hugs not bullets" approach in which security forces are less confrontational but also created a national militarized police force, the National Guard, and sent it to some of Mexico's most violent regions.Nationwide, homicides are on pace to break the record set in 2018, according to government data through August, showing that such killings had risen 3.3% to more than 23,000."You can't fight fire with fire," Lopez Obrador said Monday, according to The New York Times. "You can't fight violence with violence, you can't fight evil with evilyou have to fight evil by doing good."SEE ALSO:Mexico's rising violence and a showdown between cartels are driving a grisly trend in the country's 2nd-biggest cityJoin the conversation about this storyNOW WATCH: Here's what 'Narcos' and 'Sicario' get wrong about Mexican drug cartels Click here to read full news..