Mexico City , Mexico ( CNN ) -- The Mexican government has apologized to the families of two students killed early Friday who officials initially said were drug gang members . Jorge Antonio Mercado Alonso , 23 , and Javier Francisco Arredondo Verdugo , 24 , were mechanical engineering graduate students at the Technological Institute of Higher Learning of Monterrey , the Mexican Interior Ministry said Sunday in its apology for the shootings . Mexican soldiers chasing criminals who had fired on an army patrol shot and killed the students , the Interior Ministry said . Some of the criminals had fled onto the college campus . `` The Mexican government expresses its most deeply felt condolences to the families , '' the Interior Ministry said in a release on its Web page . The federal government will intensify its investigation to find out what happened , the ministry said . On Friday , Mexican officials had said the two dead men were part of the criminal gang that shot at the soldiers . University officials also said Friday that all students were safe . That account changed Saturday , when Mercado 's mother tried to call him after finding out about the campus shootout . When she could n't reach him , she traveled to Monterrey , where she identified her son 's body , said the campus rector , Rafael Rangel Sostman . `` I 'm certain he is with God , '' said the mother , Rosa Elvia Mercado Alonso . The school 's rector blamed himself for the mix-up in identities . `` I offer a public apology and take responsibility for having given information that ended up not being correct , '' Rangel said . `` I want to offer my most deeply felt condolences to the family of our two students and offer them our support in this difficult situation . '' Both men were scholarship students , the college said . Monterrey is in Nuevo Leon , one of two states in northeastern Mexico where drug cartel members blocked roads with hijacked vehicles Thursday and Friday to prevent military reinforcements from arriving . The criminals also set up roadblocks in neighboring Tamaulipas state . Three presumed gang members and one soldier were killed in various skirmishes over the two-day period , officials said . The area , which borders Texas , has seen bloody fighting between the Zetas and Gulf cartels after a recent gangland slaying . Hours-long gun battles are common , and U.S. officials were recently forced to temporarily close the consulate in the city of Reynosa . Mexico has been gripped in massive drug-related bloodshed since President Felipe Calderon declared war on the cartels shortly after coming into office in December 2006 . Much of the violence has taken place around Ciudad Juarez , across the border from El Paso , Texas . There are no official government tallies , but more than 16,000 people are estimated to have died in the drug wars . The vast majority of the deaths are among reputed criminals , with some police and military also being killed . Relatively few of the deaths have been civilians . Even so , the United States and Canada have issued travel warnings , particularly along the border area . The Texas Department of Public Safety took the unprecedented step this year of recommending that students on spring break not go to border areas inside Mexico . News of the violence and the travel warnings apparently have had an effect . Mexicans say tourism along the border has declined significantly this year .
Police say they were shooting down criminals who had been on an army patrol . They said some criminals had fled to Technological Institute of Higher Education of Monterrey . Initially , officials said mechanical engineering graduate students were drug gang members . Interior Ministry apologizes for deaths , promising more intense investigation .