WARSAW, Poland –  Capitalizing on low water levels in Warsaw's Vistula River, police are teaming up with archaeologists to recover gigantic marble and alabaster treasures that apparently were stolen from royals in Poland by Swedish invaders in the mid-17th century.

A police Mi-8 helicopter hovered over a riverbed on Thursday, lifting ornaments such as the centerpiece of a fountain with water outlets decorated with Satyr-like faces.

For police, it was gratifying to provide the chopper and assist Warsaw University archeologists in "this very important mission of retrieving priceless national treasures," said Mariusz Mrozek, a spokesman for Warsaw police....