(Open): Wall Street markets opened sharply lower, building on the previous session’s losses.
Nerves were unsettled after Thursday’s warning of a slowdown in economic growth from the Federal Reserve.
The Fed also expressed concern about the UK’s possible exit from the European Union.
The Dow Jones Industrial Average was down 140 points at 17,500.02 – 0.8%. The wider S&P 500 index lost 17.62 to 2,053.88.
The tech-heavy Nasdaq lost 38 points to 4,796.87.
Boeing led the losers on the Dow, falling 2.5%.