Chinese passengers walk out of the Sheremetyevo airport after being released in Moscow, Russia, March 7, 2015. [Photo/Xinhua]

MOSCOW -The Chinese Embassy to Russia confirmed that the last Chinese worker has been released by Russian customs after thorough security check.

More than 30 Chinese were detained Thursday at the Sheremetyevo airport in northwestern Moscow for bringing food materials which Russian Customs officials believed to be methamphetamine.

Chinese passengers were detained at an airport in Moscow for bringing food materials that were mistaken for drugs, the Chinese Embassy said Saturday.

Officials of the Chinese Embassy are also providing necessary assistance at the airport.

More than 30 Chinese were detained Thursday upon arrival at the Sheremetyevo airport for bringing food materials which Russian Customs officials believed to be methamphetamine.

The embassy confirmed earlier that the so-called methamphetamine turned out to be bittern, a kind of material used to make tofu.

Russian Customs Service claimed Friday that 34 Chinese citizens were detained after 230 kg of the methamphetamine-like substance was found in their luggage.