| MEXICO CITY
MEXICO CITY Mexico paraded one of its most violent drug lords on Tuesday after a police raid that President Felipe Calderon's government hopes will mark a breakthrough in its campaign against powerful cartels.
But the capture of Edgar "La Barbie" Valdez, a Texas-born 37-year-old, may do little to halt the flow of drugs into the United States or staunch bloodshed in Mexico's most violent areas, many of them along the U.S. border.
In a sign of the widening violence, eight people were killed in the Caribbean resort of Cancun early on Tuesday when suspected drug hitmen threw Molotov cocktails into a bar on the city's outskirts, the local attorney general's office said.
In Mexico City, masked police paraded a handcuffed Valdez before reporters. Wearing a green polo shirt and jeans, the man nicknamed "La Barbie" for his fair complexion grinned openly as officials discussed his capture near Mexico City on Monday.
"This operation closes a chapter in drug trafficking in Mexico," senior federal police official Facundo Rosas told local television. Six other men, including another Texan, were arrested with Valdez, and police found weapons, SUVs, cocaine and cellphones at a safe house guarded by cartel gunmen.
While the United States congratulated Mexico on the arrest, officials in Washington declined to say whether they would push for Valdez, born in Laredo, Texas, to be sent to face trial in U.S. courts where he has been indicted for drug trafficking.
"His greed and wanton disregard for human life led to his downfall," said Michele Leonhart, acting administrator of the U.S. Drug Enforcement Administration.
Yet the arrest is unlikely to end the bloodshed that presents a growing image problem for Mexico as it struggles out of recession and seeks to hold on to tourist revenues.
Over 28,000 people have died since Calderon launched his crackdown in late 2006, and the bloodshed shows no sign of stopping as gangs battle for control of smuggling routes.
Officials say Valdez, as a leader of the Beltran Leyva cartel based in central Mexico, trafficked a ton of cocaine each month and was responsible for "several dozen" murders.
He is believed to be behind merciless beheadings of rivals, torture and mutilation of victims, and the slaughter of the family of a marine who took part in the killing of his former boss Arturo Beltran Leyva in December.
But Valdez's operations were small compared to Mexico's top gangs -- the Sinaloa, Gulf and Juarez cartels -- which smuggle the majority of the 140 tons of cocaine the United Nations estimates that Mexico exports to the United States every year.
Neither is the arrest likely to end violence in border areas like Ciudad Juarez, across from El Paso, Texas, or in Mexico's wealthy northern city of Monterrey, which is being sucked into the drug war with spiraling violence this year.
"Ciudad Juarez and Monterrey were not La Barbie's area of influence, his capture won't affect violence there," said a senior federal police official who declined to be named, echoing another security official interviewed by Reuters.
Violence has begun to bleed beyond traffickers and security forces as cartels target mayors and migrants traveling north.
Suspected drug hitmen attacked federal police in Monterrey on Tuesday, sparking a gunfight and a car chase near a private university that terrified students and local residents.
Valdez's arrest follows an operation in July that killed Ignacio "Nacho" Coronel, No. 3 in the Sinaloa cartel.
While the government hopes the capture will weaken Mexican cartels, such operations in the past have at times intensified bloodshed at least temporarily as subordinates battle for control of gangs believed to rake in up to $40 billion a year.
"The investigation has not been concluded ... and at this stage it is not clear who could replace him," Rosas said.
Valdez had been a top contender to head the Beltran Leyva cartel since its boss was killed by soldiers in December.
Born into a middle-class family, Valdez is said to have played American football at school and developed a taste for luxury before coming to Mexico to work in the drug trade.
(Additional reporting by Andrew Quinn and Jeremy Pelofsky in Washington, Robin Emmott in Monterrey and Carlos Calvo in Mexico City; writing by Robin Emmott and Missy Ryan; editing by Eric Beech)