US law enforcement agencies arrested 303 people in 19 states over the past two days in the largest strike against a major Mexican drug trafficking cartel in the United States, officials said on Thursday.
Attorney General Eric Holder said the sweep against networks of the La Familia Michoacana cartel involved more than 3,000 federal, state and local law officers.
US President Barack Obama and Mexican President Felipe Calderon have vowed cooperation to fight the Mexican drug gangs. More than 14,500 people have died in drug-related violence in Mexico since Calderon launched an army-led assault on drug cartels soon after taking office in 2006.
Officials accuse La Familia of shipping large quantities of methamphetamine and cocaine to US cities from Mexico and described its operations as sophisticated and ruthless.
"It is the newest and it is the most violent of the five Mexican drug cartels," Holder said.
"The sheer level and depravity of violence that this cartel has exhibited thus far exceeds what we unfortunately have become accustomed to from the other cartels," he said.
La Familia was different from the other Mexican drug gangs in its use of religion to further its goals and it prohibits members from using illegal drugs, officials said.
"We are fighting an organization whose brutal violence is driven by so-called 'divine justice," said Michele Leonhart, acting administrator of the Drug Enforcement Administration.
La Familia has declared that it does not kill for money and does not kill innocent people in Mexico. "However, their delivery of that message was accompanied by five severed heads rolled onto a dance floor," Leonhart said.
"Today we have all taken a step forward to disrupt a group that hides behind a shield of ideology while terrorizing communities in Mexico and peddling drugs in our neighborhoods here in the United States," FBI Director Robert Mueller said.
La Familia has transformed in recent years "from a drug cartel to a sophisticated criminal organization" based in southwestern Mexico, he said.
In the United States, the cartel is developing strongholds in Los Angeles, Atlanta, Dallas and Seattle, officials said, describing those arrested this week as foot soldiers to regional managers, with the top leaders living in Mexico.
The arrests were part of a 44-month investigation known as "Project Coronado," which has led to the detention of nearly 1,200 people on drug-related charges and the seizure of more than 11.7 tons of illegal narcotics, Holder said.
Since the start of Coronado, US authorities have seized $32 million in cash, 2,700 lb (1,225 kg) of methamphetamine, 4,410 lb (2,000 kg) of cocaine and 29 lb (13 kg) of heroin.
Over the past two days alone they seized nearly 400 weapons, including a homemade grenade, Holder said.
"No one strike is going to bring an immediate end to the cartels, but these sustained direct blows to the heart of cartel operations in the United States are making a difference," Holder said.
Authorities in Mexico announced the capture of six hitmen linked to La Familia in the colonial city of Morelia as well as the arrest of a man they accuse of being a paymaster for the Zetas, the armed wing of the Gulf Cartel.
Mexican officials were unable to say if the arrests were linked to the US operation.