US President Barack Obama is holding talks in Mexico as his administration increases efforts to tackle Mexico's violent drug cartels.
The overnight visit, starting on Thursday, is Mr Obama's first to Latin America since taking office in January.
The visit includes talks with his Mexican counterpart, Felipe Calderon, who has gambled his presidency on the battle against drug traffickers. The economic crisis was also set to top the agenda.
Some 7,000 people have died since the start of last year in violence between Mexican cartels and security forces, which is spilling across the US border.
Sixteen people died in a shootout between suspected drug hitmen and soldiers in Guerrero in southwest Mexico late on Wednesday
Mr Obama's trip follows a wave of high-level US visits south of the border, which have marked a shift in the US stance toward Mexico and its trafficking problem since he took office in January.
On the eve of his visit, the president placed sanctions on three drug cartels and named a top US official to stiffen enforcement on the southern US border.