A fish porter carries a fresh tuna at the General Santos Fish Port Complex in the Philippines, on Jan 23, 2012. [Photo/CFP]

Edith O'Brien, assistant treasurer with MF Global Inc, right, stands in an elevator after invoking her Fifth Amendment right and departing from a House Financial Services subcommittee hearing in Washington, D.C., US, on March 28, 2012. O'Brien, the Chicago-based treasurer of MF Global Holdings Ltd.'s broker-dealer, was pulled from back-office obscurity onto center stage last year in testimony to Congress by former chief executive Jon S. Corzine. [Photo/CFP]