More than 4,000 archaeological artefacts looted from Mexico and seized in the US have been returned in what experts say is one of the largest repatriations between the neighbouring countries.
The items mostly date from before European explorers landed in North America and include items from hunter-gatherers in precolumbian northern Mexico, such as stones used to grind corn, statues, figurines and copper hatchets, said Pedro Sanchez, president of the National Archaeological Council of Mexico.
Seizures were made in El Paso, Phoenix, Chicago, Denver, San Diego and San Antonio by US Immigration and Customs Enforcement agents, though most of the relics - including items traced to a 2008 theft of a museum in Mexico - turned up in Fort Stockton, a Texas town about 230 miles south east of El Paso.
More than two dozen pieces of pottery were seized in Kalispell, Montana, where Homeland Security agents discovered that a consignor had paid Mexican Indians to loot items from burial sites deep in the Mexican Copper Canyon in Chihuahua, Mexico, authorities said.
Although most of the items turned over are arrowheads, several are of "incalculable archaeological value", Mr Sanchez said.
US officials displayed the relics at the Mexican Consulate in El Paso before handing them over during a ceremony. Mr Sanchez said it was the biggest archaeological repatriation, in terms of the number of items, that the US has made to Mexico.
Most of the items resulted from a string of seizures in West Texas in 2009, following a tip about relics illegally entering the US at a border crossing in Presidio, Texas.
Homeland Security special agent Dennis Ulrich said authorities executing a search warrant in Fort Stockton found the largest portion of the cache. And further investigation revealed that the two men who organised the artefacts' smuggling were involved in drug trafficking from Mexico to the US, he said.
Mr Sanchez said some of the relics found in Fort Stockton were stolen from a private collection at the Cuatro Cienagas museum in the Mexican state of Coahuila.
The items also include arrows, hunting bows and even extremely well conserved textile items such as sandals and pieces of baskets.