U.S. President Barack Obama and Mexico's President Felipe Calderon review an honour guard during an official welcoming ceremony at the presidential residence in Mexico City on Thursday. (Daniel Aguilar/Reuters)

A shootout between Mexican troops and a convoy of gunmen left 15 assailants and one soldier dead hours before U.S. President Barack Obama arrived in the country to show his support for the fight against drug cartels.

The gunfight happened in a remote, mountainous region in Guerrero state, where the Pacific coast resort of Acapulco is located, Mexico's Defence Department said in a statement Thursday.

Soldiers came under fire from a convoy of gunmen on Wednesday while patrolling the drug trafficking hotbed. One was killed and another wounded in the firefight near the town of San Nicolás del Oro.

Troops later seized two .50 calibre Barrett rifles, 17 other rifles, eight grenades, two handguns, ammunition and eight vehicles.

Obama met Thursday in the capital with President Felipe Calderon, who has sent more than 45,000 troops to drug hotspots since taking office in 2006.

More than 10,670 people have died in drug violence since then, about 10 per cent of them police and troops killed in the line of duty. The rest have been smugglers, many killed by rival gang members, the government said.

Coastal resort deaths linked to drug trade

Other deaths due to drug violence on the eve of Obama's visit included three young men whose bodies were stuffed into the trunk of a car abandoned along a highway between Acapulco and Zihuatanejo, another Pacific resort where traffickers have recently been attacking police with grenades and high-powered weapons.

The men had been beaten, tortured and strangled to death, state police said.

Elsewhere, a group of masked gunmen killed two men in military uniforms early Thursday in a remote jungle area near the Guatemalan border.

Police in the nearby town of La Trinitaria said the victims were soldiers, but the defence department did not immediately confirm that. Traffickers sometimes wear military uniforms to avert security.

Drug violence tops the agenda for Calderon and Obama, who has vowed to send hundreds of agents to the U.S. border to stem the flow of guns and money to cartels. Both governments say most illegal guns seized in Mexico come from the United States.

Calderon also wants the United States to reinstate an assault weapons ban that expired in 2004, but Obama is not expected to do that.

Spy school in the works

Meanwhile, Mexico said it will open a spy school, create a secured, internal database and improve intelligence-gathering systems to strengthen national security.

The school will be run by the government's spy agency, the Center for National Security and Investigation, known in Spanish as Cisen, the Interior Department said Thursday.

Created in 1989, Cisen allegedly once spied on political opponents of the Institutional Revolutionary Party, which ruled Mexico for 71 years until 2000.

Calderon's office says the government needs better intelligence to go after Mexico's cartels. Cisen has been weakened by years of budget cuts, his office said.