Six U.S. soldiers and a Turk were quarantined in a Turkish hospital after a suspicious powder was found in a parcel at Istanbul's main airport, local media reported Friday.

Laboratory experts were set to analyze the substance on suspicion that it might be anthrax, Anatolia news agency said.

The result was expected over the weekend.

One of the U.S. soldiers discovered the powder when he opened a parcel, part of a shipment that the group had been assigned to pick up at Istanbul's Ataturk Airport Thursday, the agency reported.

The U.S. soldiers and the Turk were serving at a NATO mission in Turkey, it said.