Geopolitical turmoil keeps Wall Street in check

NEW YORK (Reuters) - U.S. stocks extended a recent rally on Monday but finished the session short of earlier gains after several people were killed by a truck driven into a Christmas market in Germany.

The Dow Jones industrial average <.DJI> rose 40.13 points, or 0.2 percent, to 19,883.54, the S&P 500 <.SPX> gained 4.46 points, or 0.20 percent, to 2,262.53 and the Nasdaq Composite <.IXIC> added 20.28 points, or 0.37 percent, to 5,457.44.

Earlier, indexes had pared gains after the Russian ambassador to Turkey was shot dead in Ankara.

(Reporting by Noel Randewich; Editing by James Dalgleish)