In August 2007, two Mexicans tried to get their brother into the United States illegally, by hiring a people trafficker or "coyote" for a fee of 2,500 dollars for the journey. But the would-be migrant never got across the border, and the money disappeared.
When the migrant reached the northern Mexican city of Tijuana, on the border with the United States, his brothers - one of whom lived in San Francisco, California - transferred 2,500 dollars via Western Union to the "coyote" to pay for the border crossing. They withheld the transfer control number to avoid a swindle.
However, the money was collected without their brother arriving in the United States, and they were unable to recover it in spite of their complaint to Western Union, according to a story published on the Spanish language web site Apestan.com, which denounces corporate scams.
According to human rights groups that work on behalf of the rights of migrants, Western Union has become a channel for the transfer of ransom payments for undocumented people kidnapped in Mexico.
Human rights defenders are demanding that the Englewood, Colorado-based company and the Mexican authorities exert greater vigilance over money transfers.
"The only way to collect ransom payments is through Western Union, because it has branches in so many towns. The kidnappers need a collection mechanism that will not trigger the detection systems that identify suspicious money transfers," Mexican priest Luis Nieto, founder of the Catholic non-governmental organisation Nuestros Lazos de Sangre (Our Blood Ties) and an activist for migrants' rights for over 10 years, told IPS.
Nieto has created a database of Salvadorans and Hondurans who have vanished in Mexico, complete with names, dates and places where they went missing, and contact numbers.
An estimated 500,000 Latin Americans – mainly from the Central American countries of Guatemala, Honduras and El Salvador – traverse Mexico every year en route to the United States, according to NGOs and experts. Along the way, many suffer abuse and violence at the hands of police and criminal organisations.
The main migration trail goes through the states of Tabasco, Chiapas, Oaxaca, Veracruz and Tamaulipas, from southeast to northeast Mexico, a route where Western Union offices abound. The Mexican government has identified 25 municipalities between the country's southern and northern borders that are particularly dangerous for undocumented migrants.
In the last year, kidnappings of undocumented migrants have soared, with dire consequences. In August 2010, the bodies of 72 migrants, most of them Central Americans, were found in Tamaulipas state, where they had been murdered by members of Los Zetas, a drug cartel that is heavily involved in the kidnapping for ransom racket.
In December, another 40 undocumented persons were kidnapped in Oaxaca, and disappeared without a trace.
Another group of at least 80 mostly Central American migrants was kidnapped June 24 in the southeastern state of Veracruz; again, their location is unknown.
Mexico's National Human Rights Commission (CNDH) says 20,000 migrants were kidnapped in 2010. Ransom demands were between 1,500 and 5,000 dollars per person, according to the Commission.
"We have received complaints against Western Union, claiming some personnel have acted in ways indicating their involvement in money transfers for people trafficking," Joshua Hoyt, head of the Illinois Coalition for Immigrant and Refugee Rights (ICIRR), told IPS.
"The company is hypersensitive to this kind of accusation, so demands in either country for investigations into complicity in these sorts of crimes will have a big effect on them," he said.
ICIRR confronted Western Union over the confiscation of at least 17 million dollars in transfers between Mexico and the United States that were seized on the presumption that they were linked to human trafficking. Although the majority of these transfers were legitimate, the confiscated funds have not been returned to their rightful owners.
In February 2010, the US border state of Arizona's Attorney General's Office (AGO), which had brought a lawsuit against Western Union over the transfer operations, reached an agreement under which the company paid the state government a settlement of 94 million dollars.
In 2002, the Arizona AGO instituted enquiries into transfers larger than 750 dollars, and Western Union handed over lists with the names of senders and recipients of remittances for amounts between 800 and 1,200 dollars.
A 2003 seizure warrant issued by the AGO listed 142 names of people who received thousands of dollars in dozens of wire transfers, some of whom collected as much as 400,000 to 883,000 dollars.
In 2010, Western Union conducted 214 million money transfers totalling 76 billion dollars.
The company, which has 445,000 agent locations worldwide, did not respond to enquiries from IPS.
In the first quarter of this year, the US government released information from its investigations to Mexican government officials, including names, dates, amounts of ransom payments transferred by victims' relatives, and where the money was collected.
"There may be complicity of company employees in the transfer and collection of ransom payments," said Nieto, whose work has spread over the area from the United States to Central America. "In many cases where relatives say they have made payments, the kidnappers have asked the relatives to make the transfers via Western Union and to send the transfer control number. The company can definitely identify irregular transfers," he said.
Human rights activists believe it would be feasible for families of kidnap victims to sue Western Union for failing to properly monitor money transfers.
"If the relatives brought a lawsuit it could be very successful; at any rate it would be powerful leverage for negotiation," said Hoyt.