US stocks slid yesterday, pulled lower by worries over North Korea's test-firing of a barrage of missiles and concerns that strength in the labour market may persuade the Federal Reserve to keep raising interest rates.

Defying international warnings, North Korea launched at least six missiles in the early morning and a seventh some 12 hours later.

A strong private-sector jobs report - released two days before the government's highly anticipated monthly jobs report - tempered hopes for a pause in interest-rate hikes. Meanwhile, a jump in US crude oil prices to a record $75.40 a barrel stirred inflationary concerns.

The Nasdaq fell 1.69 per cent, pressured by selling in such technology bellwethers as Microsoft, Apple Computer and Intel. "The big story is North Korea," said Mike Driscoll of Bear Stearns. "One thing the stock market hates is uncertainty. North Korea adds an additional element of uncertainty to what was already an uncertain world, with Iran and Iraq."

The Dow Jones industrial average was down 76.20 points, or 0.68 per cent, at 11,151.82.

The Standard & Poor's 500 Index was down 9.28 points, or 0.72 per cent, at 1,270.91.

The Nasdaq Composite Index was down 37.10 points, or 1.69 per cent, at 2,153.34.

The monthly ADP National Employment Report, showing strong private-sector employment in June, added to the market's jitters. The report sharply boosted expectations that the Federal Reserve will raise rates at its August policy-setting meeting - six days after it most recent policy statement had stirred hopes of a possible pause. Investors worry that higher interest rates will hurt consumer spending, slow down the economy and stifle the growth of corporate profits.

Shares of companies sensitive to economic cycles led the sell-off, with shares of heavy equipment maker Caterpillar, down 2.19 per cent at $73.13 on the NYSE. The stock was the biggest drag on the Dow, followed by Boeing, down 1.39 per cent at $80.17.

On Nasdaq, Apple shares fell 1.64 per cent to $57.00, while Microsoft shares fell 1.48 per cent to $23.35. The software maker was the second-biggest drag on the S&P 500, ranking only behind Intel, whose shares fell 3.15 per cent to $18.75.

Crude oil for August delivery soared to a record $75.40 a barrel, up more than 1 per cent, on the New York Mercantile Exchange, amid expectations of a surge in US demand and concerns about global political tensions.