MEXICO CITY Investigators said Saturday they have found 51 corpses in two days of digging in a field near a trash dump outside the northern city of Monterrey, as excavations continued at one of the largest clandestine body dumping grounds in Mexico's *lo**y drug war.

The attorney general of Nuevo Leon state, where Monterrey is located, said the victims included 48 men and 3 women. There so many bodies that authorities were using refrigerated trucks to hold them, Alejandro Garza y Garza told local television.

Investigators are still struggling to identify the remains but suspect drug traffickers are involved.

"The majority of these bodies have tattoos of different types that could give us an indication about whether they belonged to one group or another and, among other things, determine whether they were linked to organized crime," Garza y Garza said.

He added that investigators were nearing the end of their search.

"We have practically covered all the area where we think there might be this sort of thing," Garza y Garza said. "In general terms, we are wrapping it up."

A state government spokesman said the bodies have been found both whole and in parts, with some buried in pits and others on or near the surface. The spokesman, who was not authorized to be quoted by name, said an anonymous phone tip led authorities to the site on Thursday.