Oil slumps after partial returns in UK indicate Brexit

By Aaron Sheldrick TOKYO (Reuters) - Oil prices slumped more than 4 percent in Asian trading after results so far from a British referendum on European Union membership showed the "Leave" camp holding a lead. Brent crude was down $2.39 at $48.52 a barrel. On Thursday, both contracts rose sharply, rallying on optimism that Britons would vote to stay in Europe.