Stocks extended losses on Friday, with the Nasdaq briefly falling more than 1 percent on renewed fears about the European debt crisis.

The Dow Jones industrial average <.DJI> was down 99.22 points, or 0.82 percent, at 11,950.78. The Standard & Poor's 500 Index <.SPX> was down 10.46 points, or 0.81 percent, at 1,273.04. The Nasdaq Composite Index <.IXIC> was down 24.40 points, or 0.91 percent, at 2,662.35.

A brief suspension in the trading of some big Italian banks and nervousness over Greece's ability to execute austerity measures raised new concerns about the European debt crisis.

(Reporting by Angela Moon)