US stocks extended losses in early trading on Thursday, with the Dow tumbling more than 1,500 points and the Nasdaq plunging more than 1,000 points. US President Donald Trump announced additional "reciprocal tariffs" of 10% to 49% on almost all countries, a move that threatens to spark a global trade war and hit an already weak US economy hard. The number of Americans claiming unemployment benefits unexpectedly fell last week. Trump's tariffs and OPEC + production plan sent oil prices tumbling. The Dow fell 1,543.14 points, or 3.65%, to 40,682.18; the Nasdaq fell 1,004.16 points, or 5.71%, to 16,596.89; the S & P 500 fell 246.47 points, or 4.35%, to 5,424.50.