Last year it launched a search-and-rescue unit, Borstar, to criss-cross the region looking for immigrants in trouble.

ECONOMIST: Illegal immigration: Worth dying for | The

Last month, near the small town of Ajo, Borstar agents found two Mexican men on the brink of death under a mesquite bush.

ECONOMIST: Illegal immigration

Acting, in most cases, on tip-offs from members of groups who have managed to survive, the Borstar team has made over 1, 000 rescues this year, up from just below 300 in 1999.

ECONOMIST: Illegal immigration