SAO PAULO, Brazil -- Brazil's justice ministry is asking the main hotel chains in the country to explain the high prices being charged for rooms during the 2014 World Cup.

The request comes after several complaints from consumer advocates and a study by the country's tourism board which showed that exorbitant prices will be charged during the monthlong tournament next year.

Among the companies notified by the ministry's consumer rights secretariat on Thursday are Accor, Choice, Louvre, Blue Tree, Nacional Inn, Wyndham, IHG and Bourbon. The Brazilian Association of the Hotel Industry also was notified.

The ministry said Friday that the companies have 48 hours to respond to the request.

"Tourists are consumers which require special protection because they are outside of their city or country," Amaury Oliva, director of the ministry's consumer rights secretariat, said in a statement. "We are working to make sure that they are well received and that the services we provide have quality and fair price."

The ministry said it wants the hotel chains to provide the average rates charged in the past during other high-demand events in the 12 World Cup host cities, so they can be compared to the prices for the tournament. Although price increases are expected during special events such as the World Cup, officials suspect the chains might be overcharging more than usual this time.

Calls to the Brazilian Association of the Hotel Industry were not immediately answered on Friday.

The tourism board, or Embratur, this year showed that rates will rise up to 500 per cent during the World Cup in some hotels offered by the FIFA-appointed agency MATCH Services, prompting several consumer rights groups to demand action from the government.

Brazilian President Dilma Rousseff last month created a committee to monitor abusive price hikes of hotel rates and plane tickets during football's showcase event.

The government also said it will investigate whether MATCH, FIFA's official accommodation agency, was involved in "cartel" practices that may lead to price hikes during the World Cup, a claim that FIFA and MATCH have repeatedly denied.

Brazil sports minister Aldo Rebelo, the government official in charge of preparations for the World Cup and the 2016 Rio Olympics, earlier this year pledged "zero tolerance" for hotels charging abusive room rates. He said significant hikes would hurt Brazil's image abroad and threaten to scare tourists away.

Although Brazil has said it will not try to control market prices, Rebelo warned that hotels that raised prices excessively would feel the "heavy hand" of the law, adding that consequences included possible hotel closures.

Brazil is expecting 600,000 foreigners and about 3 million local visitors travelling through the 12 host cities and the rest of the country next June, when it will host the World Cup for the first time since 1950.