Mexico City ( CNN ) -- Federal police have arrested a man they believe is responsible for coordinating the kidnappings of more than 70 migrants later found dead in northern Mexico last year , authorities said Friday . Edgar Huerta , 22 , was arrested with his girlfriend Thursday in the central northern state of Zacatecas . Huerta told authorities he was responsible for the August abductions of more than 70 undocumented immigrants , later found dead in the northern border state of Tamaulipas , authorities said after his arrest . He also reportedly told officials that he had killed 10 people . Violence is common in Tamaulipas , where authorities are battling rival drug cartels . The Gulf cartel and the Zetas cartel used to work together , but split more than a year ago and are now fighting for control of lucrative smuggling routes into the United States . Huerta is accused of running with the Zetas and reportedly told authorities that he had directed the kidnappings of passengers on at least six buses near San Fernando , a town in Tamaulipas . The passengers were then allegedly taken to area safe houses and tortured to see whether they belonged to the rival Gulf cartel . The growing reach of the cartels has increased the risk for migrants crossing through Mexico to get to the United States , Mexico 's National Commission for Human Rights has said . An investigation by the commission showed that 9,758 migrants were abducted from September 2008 to February 2009 , or about 1,600 per month . The bodies of 72 migrants from Central and South America were discovered at a ranch near San Fernando in August . In the same area , authorities found mass graves this year , containing the remains of nearly 200 people . They began finding the graves while investigating the kidnapping of passengers from a bus in late March . The Zetas have been blamed for the mass graves and for the deaths of the 72 migrants found last year . Nationwide , there have been some 35,000 drug-related deaths since President Felipe Calderon began a crackdown on the cartels in December 2006 , the Mexican government says .
Edgar Huerta was arrested last year with his girlfriend . Authorities say he confessed to directing the kidnappings of 10 migrants Thursday . He reportedly told authorities he had killed more than 70 people . Edgar Huerta is accused of belonging to the Zetas drug cartel .