More than 6 million dollars worth of Samsung Electronics were stolen by thieves at a factory near Sao Paulo, Brazil, with assailants holding workers hostage as they took off with devices, including smartphones, tablets and notebook computers.

Samsung says the products taken are worth $6.3 million, making it one of the largest tech heists and comes as the 2014 FIFA World Cup in the South American country winds down.

According to police reports, the robbery took place after a carjacking of a shuttle that was used to move factory workers. It lasted nearly four hours in the Campinas industrial area of the southeast part of the state.

"They subdued the guards, took their weapons and their ammunition and told them to continue working as if nothing had happened," police Lt. Vitor Chaves was quoted as saying. Some workers were held captive in a separate area and others were told to hand over their phones, so they wouldn't call the police.

A public security spokesman for the government reported that the thieves took off with seven trucks full of the more than 40,000 Samsung products. Police are currently investigating the incident, but said no suspects have thus far been identified.

"We have cooperated fully with the police investigation that is underway and will do our best to avoid any sort of repeat incident," said Samsung Eletronica da Amazonia Ltda., the manufacturing unit of the Korean electronics giant in Brazil, in a statement.

According to employees, the attackers were armed and disarmed the security guards on the premise before moving into the factory and taking the 50 employees hostage as the heist took place. All phones, including smartphones, were disabled during the robbery.

There were over a dozen assailants, including the drivers of the trucks, and reportedly communicated with one another via radio and mobile phones.

The initial estimate of value of the products stolen was put forward to be around $36 million by police, but Samsung lowered that estimation after finding out what was taken.

The hostages were not harmed.

Crime in Brazil remains one of the country's nagging issues, and has been highlighted by the hosting of the World Cup, where tens of thousands of workers have staged near constant protests over the amount of money being spent to host the four week event, even as the country struggles to overcome economic stagnation and a massive divide in wealth among the population.

A number of workers were killed in the construction of the stadiums where matches are being held. Still, police say this is unrelated to World Cup unrest and was largely planned for weeks in advance.