text: Norway Searches for Treasured Masterpieces OSLO, Norway - Police launched a nationwide investigation Monday for armed robbers who barged into a lightly guarded Oslo museum and ripped the Edvard Munch masterpiece "The Scream" and another painting from the walls, as stunned visitors watched in disbelief.    The paintings were stolen from Oslo's Munch Museum on Sunday by masked, armed thieves who pulled them from the walls as visitors and staff watched in shock...