Mexico detained 73 percent more migrants since the announcement of an operation to shore up security on its Southern Border, according to a study released Wednesday by human rights and migrants' advocates groups.
The study found that about 168,000 migrants were detained in Mexico from July 2014 to June of this year, up from some 97,000 during the previous 12-month period.
It was based on a government data, case documentation from migrants' shelters, interviews with authorities, migrants and advocates and other sources.
Mexico announced its Southern Border Program in the summer of 2014, a time when the United States was experiencing a large spike in unaccompanied child migrants arriving at its own southern border. Many were Central American children fleeing violence in their home countries.
The Washington Office on Latin America, or WOLA, a U.S.-based advocacy group which helped prepare the report, said in an executive summary that the increased migration enforcement has "worrying implications" for human rights, due to reports of migrants being injured or killed during operations.
It also said that the crackdown has led migrants to abandon established northward routes such as the train known as "the beast," and resort instead to riskier, clandestine avenues where they are more vulnerable, such as traveling by foot or water.
The summary warned of persisting "patterns of crimes against migrants, including kidnappings, human trafficking, robbery, assault and extortion, along with human rights violations against migrants, especially during apprehension and deportation processes."
WOLA noted that punishment for abuses of migrants is rare, with just four of the more than 1,600 complaints received by the National Human Rights Commission during a three-year period through this past June resulting in formal recommendations to government entities implicated in possible abuses.