(Bloomberg) -- A Nigerian social-media celebrity helped North Korean hackers launder money stolen from a Maltese bank, U.S. officials said. Ramon Olorunwa Abbas played a supporting role in cyber-scams perpetrated by three computer programmers accused of extorting more than $1.3 billion of cash and cryptocurrency, the Justice Department said on Feb. 17. Abbas, who is widely known as “Hushpuppi” and is in U.S. custody while awaiting trial, has 2.5...