Vallejo Guarin was arrested outside a luxury hotel in central Madrid with the collaboration of the U.S. Drug Enforcement Administration , the Spanish Civil Guard said in a news release . Drug trafficker on U.S. State Department most wanted list is arrested in Spain . The arrest of the man who was once a top drug kingpin for Mexico's Sinaloa cartel comes as Mexico and the United States are engaged in an escalating war against cartels that has killed more than 100,000 U.S. says he heads one of South America 's most violent drugs operations . U.S. State Department had offered a $ 5 million reward for his arrest .
Drug trafficker on U.S. State Department most wanted list is arrested in Spain . The arrest of the man who was once a top drug kingpin for Mexico's Sinaloa cartel comes as Mexico and the United States are engaged in an escalating war against cartels that has killed more than 100,000 U.S. says he heads one of South America 's most violent drugs operations . U.S. State Department had offered a $ 5 million reward for his arrest .