Apparently the reason for today's market weakness can be traced to Portugal, and one of the banks there. Their shares were suspended earlier today following concerns about accounting irregularities at its parent group.
One look at the chart of Banco Espirito Santo below will show it has been a clear avoid for most people for a while, and no doubt some people have been profiting from the downtrend which started in April. Those trying to pick the bottom in this price move, or who like trying to catch falling knives have suffered again. Another case perhaps of price preceding news?