SAO PAULO-Armed police impersonators stole more than 1,600 pounds of precious metals, valued at $40 million, from Brazil’s Sao Paulo Airport, taking two hostages in the process.

Men dressed as Brazilian federal police officers arrived at Guarulhos airport Thursday in vehicles outfitted with fraudulent law enforcement markings. The armed thieves then proceeded to order airport workers to fill a pickup truck with gold and other precious metals before departing with two hostages, Reuters reported.

Airport officials confirmed to Reuters no one was injured during the robbery, but did not comment on the status of the hostages.

The thieves may have kidnapped a senior airport official on Wednesday, holding him for 12 hours to gain information about the shipment of valuable metals, reported Fox News. Four children related to the official may have also been kidnapped to gain information.

There are at least four suspects. A local Brazilian broadcaster said the perpetrators abandoned the fake police vehicles in a neighbourhood 12 miles from the airport, reported Fox. All suspects remain at large.

The shipment of precious metals was originally intended for New York and Zurich, according to the Evening Standard.

Security footage showed the suspects arriving at Guarulhos airport in a black pickup truck resembling Brazil’s federal police. Four masked men exited the vehicle, and at least one of them had a rifle. They proceeded to confront the airport workers and forced them to move gold in the pickup truck.

According to police report, the thieves left with about 1,650 pounds of gold and other precious metals.

The Brazilian news outlet Globo.com reported the thieves kept the dispatcher and his family hostage the night before the heist and were able to gain insider information.

The airport is operated by GRU Airport, a consortium that includes Invepar, Airports Company South Africa, and state airport operator Infraero. Sao Paulo airport is one of the busiest airports in South America.