Thieves raided a Samsung electronics factory in Brazil during the night shift early Monday, subdued workers and guards, and made off with at least $6 million worth of cellphones and computers, according to The Associated Press.

The gang of heavily armed men captured eight plant employees as they neared the factory in a company bus just before midnight, said civil police in Sao Paulo state, the AP reported. They stole the workers' ID tags and took two of them with them as hostages as they entered the factory in the college town of Campinas.

Once inside, the gang overpowered security guards and spent more than three hours in the plant, trucking out the electronics, according to the AP. The remaining six employees were taken to an unknown location.

"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 told the Globo television, the AP reported. 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.

In total, police suspect that 20 robbers participated, carting out more than 40,000 finished products in seven trucks, according to the AP.

Police had estimated the value of the stolen goods at $36 million, but Samsung later put the figure at $6 million, the AP reported. Investigators are looking at security video around the South Korean company's facility north of Sao Paulo to see if they can identify the thieves,

Samsung said in a statement that it was "very worried about the incident," but clarified that none of the employees were hurt, according to the AP.

"We are fully cooperating with the ongoing police investigation, and we will do our best to prevent this happening again," the statement said, the AP reported.