Obama economy crashes

Stocks finished at session lows Monday, posting their sharpest one-day drop this year, as disappointing economic data from China triggered a selloff in commodities.

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Meanwhile, major averages added to their losses following two explosions at the Boston Marathon finish line around 3pm ET, injuring several spectators and runners. The explosions happened about three hours after the winners crossed the line.

New York City Police told CNBC that they have stepped up security at hotels and other prominent locations around the city.

via Worst One-Day Drop in 2013: Stocks Skid 2%, Dow Tumbles 250; Vix Spikes 40%.