Dozens of migrants found stranded in Arizona desert

The perilous and deadly nature of the illegal immigration taking place on the US's southern border has been further highlighted by the discovery of around 70 people left stranded by "coyotes" in the middle of desert.

The migrants - many of whom were badly dehydrated - had run out of water and said three of their number had already died, though officials have not yet discovered any bodies.

The migrants, mainly from Guatemala, were discovered on Tuesday near Tonopah in central Arizona, 50 miles west of Phoenix, by a police officer who was approached by the group. They told him they had spent three days in the desert, with the temperature above 100F (38C) and with no supplies.

Sheriff Joe Arpaio told the Los Angeles Times: "We've got all this surveillance and vigilance on the border and they're still coming. I'm not going to let these people come through this county." The US Customs and Border Protection department says it annually intercepts 1.1 million illegal migrants trying to enter the US from Mexico. It is widely estimated that every year around 500,000 succeed.

In recent years the US has tried to strengthen the border with extra officers and soldiers. But campaigners say this has pushed migrants to attempt the crossing in increasingly remote and dangerous areas. Since 2000 around 500 migrants each year are known to have died.

Investigators want to know why the migrants found on Tuesday were abandoned. One theory is that they were driven there by one team of smugglers and were due to be picked up by another group.

Nine of the migrants were still in hospital yesterday, being treated for dehydration. The migrants will have their cases heard by an immigration judge who will decide whether they can remain in the US or must be deported.