ROME — Two Japanese nationals were detained by Italian financial police last week after trying to enter Switzerland with $134 billion worth of undeclared U.S. bonds, mostly Treasury bonds, an Italian daily said Wednesday. The Japanese consulate general in Milan confirmed that the detention had taken place and said it was trying to confirm with Italian authorities whether the two were indeed Japanese nationals and their identities. According to the report in il Giornale, two unidentified Japanese in their 50s concealed the bonds, including 249 U.S. Treasury bonds each worth $500 million, in a suitcase with a false bottom that...