Acapulco , Mexico ( CNN ) -- Arrests could come as early as this week in the alleged rape of six Spanish tourists in Acapulco , the lead investigator in the case told CNN on Wednesday . Mexican authorities have identified the suspects and are monitoring them , said Marcos Juarez . Fifty investigators were working the case . The six women were among 14 people victimized by hooded gunmen who burst into a beach bungalow in the resort town before dawn Monday . There are seven suspects between the ages of 20 and 30 , Juarez said . In addition to the rapes , the men stole cell phones , iPads and tennis shoes from the victims , investigators said . Investigators believe that the victims bought drugs from one or more of the suspects a day or two earlier , and that the victims knew the suspects , Juarez said . The Spanish nationals range from 20 to 34 years of age and are under the protection of Mexican authorities in Mexico City . Rape casein Mexican resort city puts violence back in the spotlight . Seven men who were with the group were tied up with cell phone cables and bikini straps while the gunmen assaulted the six women , officials said . A seventh woman , a Mexican , was spared because of her nationality , Guerrero state Attorney General Martha Garzon said in a radio interview . `` She has said that she identified herself to the men and asked them not to rape her , '' Garzon told Radio Formula . `` And they told her that she had 'passed the test ' by being Mexican , and from that point they do n't touch her . '' The gunmen 's motive was robbery and `` to have some fun , '' as they saw it , Garzon said . They do not appear to be a part of organized crime , officials said . Military checkpoints have been set up to apprehend the suspects . As they sift through evidence , investigators have cordoned off the area around the bungalow , which is in an open area of Playa Encantada that has limited security in Playa Encantada . Last year , the city of Acapulco attracted half a million tourists -- most of them Mexicans . Mexico 's Foreign Ministry said in a statement that the Spanish tourists received consular aid after the incident . The U.S. State Department says `` resort areas and tourist destinations in Mexico generally do not see the levels of drug-related violence and crime reported in the border region and in areas along major trafficking routes . '' But the agency adds that resort city bars , including those in Acapulco , can be `` havens for drug dealers and petty criminals . '' CNN 's Miguel Marquez and Nick Parker reported from Acapulco and Mariano Castillo from Atlanta . CNN 's David Ariosto contributed to this report .
NEW : 50 detectives are working the case . Official says they are pursuing strong evidence . Two Spanish women were allegedly raped .