New York ( CNN ) -- The FBI is investigating the theft of $ 1.2 million from Swiss International Airlines Flight 17 , which arrived at New York 's JFK International Airport from Zurich , Switzerland , on Saturday afternoon , a spokesman said Tuesday . The money was in $ 100 bills , J. Peter Donald said , adding it 's still unclear when it was stolen . Flight 17 was a passenger flight with air cargo , including a shipment of currency , according to another FBI spokesman , Jim Margolin . After the plane landed , the shipment of cash was discovered to be $ 1.2 million short . Margolin said investigators have not determined whether the money was taken before the flight left Zurich . He said the cash was missing from a container that the bank uses to transfer currency , which is loaded into a larger cargo container . He said it would take a forklift to lower the currrency container into the larger container , or to remove it . How safe is your carry-on bag ? A law enforcement official with knowledge of the investigation said the money was headed to the Federal Reserve . Andrea Priest , a spokeswoman for the Federal Reserve Bank of New York , had no comment . Another law enforcement source told CNN the money belonged to a U.S. bank that was transferring currency from offices in Switzerland to the U.S . It was a transaction within the bank , but the money was passing through a Federal Reserve facility in New Jersey , according to the source , who said it 's fairly common , when large sums are transferred , even internally , for them to go through a federal facility , where old bills are exchanged for new ones . The shortfall was discovered Monday when the shipment was delivered to the Federal Reserve facility in Rutherford , New Jersey , the source said . The Port Authority is declining comment , according to spokesman Steve Coleman . Robbers breach gate , steal $ 50 million in diamonds at Belgian airport . CNN 's Ronni Berke contributed to this report .
NEW : the Federal Reserve says it would take a forklift to get the cash out of the container it 's shipped in . Money arrived at JFK International Airport from New York 's in a cargo container on Monday . It 's not clear when it was stolen , FBI says . Official says the money was headed for FBI .