A Samsung Galaxy S5 being assembled in a Samsung factory. Samsung Approximately 20 criminals disguised as Samsung employees invaded Samsung's Brazil factory in Campinas, São Paulo, stealing an estimated BRL $14 million, or USD $6.5 million, in devices.

The heist took place during the factory's night shift, with some 200 Samsung employees still in the factory while criminals loaded up seven trucks with Samsung tablets, notebooks, and smartphones, according to ZDNet.

50 factory employees were held hostage during the heist, according to a Samsung statement.

"Some employees were held hostage by the criminals while the majority continued to work, but had the batteries of their mobile phones taken to prevent them from calling the police," ZDNet reports.

Though the criminals were armed with submachine guns, no injuries have been reported and the criminals have been described by Samsung employees as "not violent at any point."

Police are currently investigating the robbery, which is thought to be an inside job due to the criminals' ease of entry and interior knowledge of the factory.

"We are very concerned about this incident," Samsung said in a statement. "Fortunately, nobody was hurt. We are fully cooperating with the ongoing police investigation, and we will do our best to avoid it happening again."

Early media reports estimated the amount of goods stolen to be approximately $36 million. Business Insider has updated these numbers to reflect more recent statements from Samsung.