A gang of masked gunmen broke into a beach bungalow and raped six Spanish women in Acapulco, a Mexican resort city on the Pacific heavily dependent on tourism revenue, officials said.

The attackers used phone cables and bikini straps to tie up seven Spanish men and a Mexican woman who were also in the rental house near the Barra Vieja beach as they assaulted the Spanish women for two hours early Monday.

The rental house is located in an area filled with restaurants and other bungalows off the beach in Acapulco, a popular tourist destination in southern Mexico.

Acapulco Mayor Luis Walton Aburto caused a stir when he told reporters that the crime was "very unfortunate, but it happens everywhere in the world."

Mexico's foreign ministry however was quick to condemn the attacks, and said the Spaniards had received proper consular assistance.

The victims were taken to Mexico City, according to Mexican media.

"This is the worst attack on tourism in Acapulco. We have not had anything like this in recent times," Roberto Manzanares, from the Guerrero state Hotel and Restaurant Association, told AFP.

The attack took place as the city is packed with tourists enjoying a holiday weekend -- the hotel association reports a 90 percent occupancy rate, as well as the arrival of cruise ships and groups of European tourists.

Tourism is one of the country's main sources of hard currency along with oil, mining and money sent by Mexicans living abroad.

Acapulco has become one of Mexico's most violent cities amid growing confrontations between drug traffickers and security forces.

But the violence rarely affects the nine million tourists -- a third of them foreigners -- who visit Acapulco each year.

More than 70,000 deaths have been attributed to drug violence nationwide since December 2006, as rival cartels fight for control of lucrative drug routes to the United States.

La Jornada newspaper said the rapists took about $600 in cash, six cell phones, two computers, three cameras, a music player and two credit cards.