U.S. officials delivered five helicopters to Mexico on Tuesday to help the country in its fight against drug cartels.
The aircraft are part of more than $604 million worth of vehicles and equipment that the U.S. plans to give Mexico in the coming months.
"The helicopters that we are handing over today are very important substantively and symbolically in our cooperation, but they are only a part of the chain of many important milestones in meeting these challenges," said John Brennan, assistant to President Barack Obama for homeland security and counterterrorism.
In addition to the more than $1.1 billion worth of aid the U.S. has pledged to provide Mexico, Brennan said U.S. and Mexican officials are planning new programs to help Mexico professionalize its police forces and strengthen its justice system.
U.S. officials are fighting drug cartels on both sides of the border, he said.
"We understand that the United States has a co-responsibility in meeting the social, international and regional challenges posed by the international cartels and narcotics trafficking," Brennan said.
The Mexican air force will use the five Bell 412 helicopters for transportation and reconnaissance, officials said.
The helicopters, worth $66 million, were funded by the U.S. government's $1.4 billion Merida Initiative, which provides resources to help Mexico, Central American nations, the Dominican Republic and Haiti combat drug trafficking.
The funds will pay for equipment such as aircraft and improved law enforcement communications networks as well as technical training to improve justice systems and expand anti-gang programs.
Since taking office in 2006, Mexican President Felipe Calderon has deployed tens of thousands of soldiers and federal police across the country seeking to crush the cartels, an offensive that has earned praise from Washington but also led to a surge in violence.
When the U.S. Congress approved the first $400 million aid installment in June 2008, more than 4,000 people had died in Mexico's drug-related violence under Calderon's watch. Three years later, the death toll stands at more than 14,000.