MEXICO CITY -- There's a new name to worry about in Mexico's ever-churning drug war.

They call themselves the New Generation of Jalisco, and they just pulled off one of the most audacious attacks against Mexican authorities in years.

Earlier this week, on a lonely road in western Mexico between the resort beach town of Puerto Vallarta and the state capital of Guadalajara, cartel henchmen with assault rifles and grenade launchers ambushed a convoy of state police, killing 15 of them and wounding five more. That brought the total number of police killed in the state to 21, just over the past three weeks, according to the Mexican newspaper El Universal.

This is not just an attack on the police, but "an attack on the security of the state, an attack on the people's security, and it's bringing crisis to the state," said Jose Guillermo Garcia Murillo, a professor at the University of Guadalajara.

Mexican cartels rise and fall, and analysts say New Generation is now rising faster than any. According to the Treasury Department, which put New Generation's leaders on the drug kingpin list this week, the cartel is operating in several Mexican states and forging underworld ties around the globe.

New Generation and an allied group, Los Cuinis, "have rapidly expanded their criminal empire in recent years through the use of violence and extortion," John E. Smith, acting director of the Office of Foreign Assets Control, said in a statement. "They now rank among the most powerful drug trafficking organizations in Mexico.”

The group is relatively new, coalescing five years ago from the remnants of another group, the Milenio cartel, after the capture of one of its leaders, according to U.S. officials. Their leader is a man named Nemesio Osegera Cervantes, a.k.a. "El Mencho," reportedly a former police officer himself. Beyond the drug trade, analysts said the cartel makes money by selling guns, stealing gasoline, extortion and kidnapping.

During the militia uprising over the past two years against the Knights Templar cartel in the neighboring state of Michoacan, the New Generation cartel was widely accused of infiltrating militia factions, providing money and weapons to fight their Templar rivals. They've also gone after the Zetas, a notorious cartel now in decline, following the capture of many of its top bosses. New Generation was also linked to the dozens of bodies found two years ago in a mass grave in the small town of La Barca, in Jalisco.

More recently, the cartel has been on a police killing spree, forcing state authorities to convene emergency meetings to address the threat. Last week, gunmen tried and failed to kill the Jalisco state security commissioner, Alejandro Solorio. After the highway ambush, the police chief in the town of Zacoalco de Torres was found dead. 

“It is spreading like a cancer in Mexico,” Mike Vigil, formerly of the Drug Enforcement Administration, told the Global Post. “It’s the fastest expanding cartel and they could in the near future overtake the Sinaloa cartel as the most significant organized group in Mexico.”

Mexican authorities said they believed the police ambush was revenge for the killing of a New Generation cartel leader, Heriberto Acevedo Cardenas, or "El Gringo," last month. But analysts also suspect that its timing has to do with Mexico's upcoming local elections in the summer.

"Its not a coincidence that this weekend [April 5], election campaigns started," said Gerson Hernandez Mecalco, a political science professor at Mexico's National Autonomous University. "It's a very negative message, on the part of organized crime, of the possible impact and strength that they continue to have."

Gabriela Martinez contributed to this report.

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