|Mexican President Felipe Calderon's has led an aggressive army-led crackdown on drug cartels [Reuters]
Mexico's military has freed 61 men being held captive and forced to work for a drug gang in a violent northern border city.
The army said on Sunday that the men were found in a safe house in Piedras Negras on Saturday.
Soldiers made the discovery during a security sweep in the area that also turned up an abandoned truck filled with 6 tons of marijuana.
A statement said one of the captive men is from Honduras, while the others are from various parts of Mexico.
Piedras Negras sits across the border from Eagle Pass, Texas, in the Mexican state of Coahuila, which has been the scene of ongoing battles between drug gangs.
Last week the army arrested a major figure from the Zetas drug cartel there.
The rescue mission comes a day after more violence hit Mexican prisons.
Twenty prisoners died and 12 others were injured on Saturday in a prison on the Mexican-US border town of Matamoros, after a dispute between two inmates turned into a melee that lasted almost three hours.
President criticises opposition
Meanwhile, Felipe Calderon, the Mexican president, said on Sunday that politicians in the main opposition party may consider deals with criminals, opening an inflammatory new front in the nation's presidential election campaign.
Calderon's blunt remarks about the centrist Institutional Revolutionary Party (PRI), which is favored to win the July 1, 2012 election, are unusual in a country where the president is expected to stay largely aloof from party politics.
Centering on the policy that has dominated his presidency - an aggressive army-led crackdown on drug cartels - his comments risk polarizing opinion on how to restore stability to Mexico, where the drug war has killed 44,000 in five years.
Leading members of Calderon's conservative National Action Party (PAN), other PRI opponents and political
analysts have accused the once-dominant party of making secret deals with drug cartels in the past to keep the peace in Mexico.
In a weekend New York Times interview published a day after he said a state governed by the PRI had been left in the hands of a drug gang, Calderon was asked whether the opposition party might pursue a corrupt relationship with organized crime.
"There are many in the PRI who think the deals of the past would work now. I don't see what deal could be done, but that is the mentality many of them have," Calderon, whom the law prevents from seeking a second six-year term, said.
Analysts say Calderon is bitterly opposed to the PRI, which dominated Mexico for seven decades until the PAN won the presidency in 2000 under its candidate Vicente Fox.
The tide of drug war killings has eroded support for the PAN, and the PRI's main hopeful, Enrique Pena Nieto, is said to have around twice the support of his nearest rival.