Mexico has demanded a full investigation into the death of one of its citizens after he was beaten and shot with electric stun guns by US border patrol agents.
The incident happened as Anastasio Hernandez was about to be deported from the US state of California.
A spokeswoman for the US Border Patrol said its officers had acted in self defence after he became violent.
Mr Hernandez had lived and worked in California for more than 20 years.
In a statement, the Mexican foreign ministry expressed its "indignation" and condemned the events that led to his death.
Mr Hernandez died in a hospital near San Diego on Monday, three days after he was beaten and shot with Taser stun guns as agents tried to deport him.
The US justice department and local police are investigating the incident.
The Border Patrol said Mr Hernandez had tried to escape when his handcuffs were removed as he was about to be deported at the San Ysidro border crossing, and agents had used appropriate force to subdue him.
But Mexican human rights groups said agents had been seen beating him even after he stopped moving.
Mr Hernandez had worked in the San Diego area for more than 20 years without the proper documents, and had five children.
Mexicans make up three-quarters of the estimated 12 million illegal immigrants living in the US, and the issue has long been a source of tension between the two neighbours.
Hundreds of thousands of Mexicans are deported or voluntarily repatriated from the US each year.