. >> some referred art work referred in the bay area, considered by poleland to be a national treasure>> we're talking about 75 paintings worth about a million dollars. the fbi is releasing details about the case. >> cally was a polish resistance fighter. sheful aed the world, painting. the art work is considered a national treasure in poland when she died in 1998 she left 86 paintings to the polish museum in rappersville, switzerland. >> art works never reached their intended destination. >> they vanished. for 16 years, a mistery. four years ago the museum intensified the search for the work. in mid january polish ministry of culture turned to the fbi in san francisco. >> the polish government asked us to try to reach fourt a family member here in the bay area to see if he was aware. >> the fbi want to his nephew's home. >> he knew where they were. they were being maintained in storage. and after a conversation it was agreed that we'd take them and get them back to switzerland >> the fbi recovered 75 of the 86 paintings the nephew said he was protecting the paintings and didn't know t