Since January 1, some 230 drug slayings have occurred around Juarez, Mexico's murder capital. Compare that to 75 this time last year, and you get a sense of the exploding violence, CBS News correspondent Bill Whitaker reports.
Vicious cartels are battling to control the $14 billion a year illicit trade feeding an insatiable U.S. appetite for drugs. Mexican authorities are hitting the cartels with all they have.
Soldiers stormed a Juarez warehouse last week, seizing two tons of marijuana. Tuesday 10 gangsters were arrested in Mexico City with their cache of guns and grenades.
But the gangs have the money and the weapons to fight back.
"While drugs are being smuggled north, a lot of guns are going south," said Brian Jenkins, a terrorism expert at Rand Corp.
By U.S. estimates, 95 percent of cartel guns are smuggled from the states - 2,000 a day according to a recent investigation.
Janet Napolitano, the new head of Homeland Security, has ordered a crackdown on gun smuggling. On the streets of Juarez, it feels like war.
"It's such a huge fight that I don't think it will end," said Juarez resident Ricardo Felix. "It's going to continue until one of the cartels takes control of the country."
They had taken control of Villa Ahumada, the desert town where 21 died Tuesday.
Troops came in last year after traffickers killed three police chiefs, and forced the mayor to flee. Tijuana journalist, Vicente Calderon, says the government was slow to react the cartels' growing threat.
"The government used to tell us this is just a problem among drug cartels," said Calderon. "During the last two years, it's coming out into the surface and affecting everybody else."
With more than 6,000 slayings, 2008 was Mexico's most deadly year for drug violence.
This year is starting to look even worse.