NEW YORK, Nov 20, 2008 (AFP) - US stocks extended losses at the opening Thursday as more weak economic data kept the mood somber a day after the main indexes plunged to five-and-a-half-year lows.

The opening losses were modest however after a global rout that saw a slide of 6.89 percent in Tokyo and hefty declines in Europe.

In the first trades on Wall Street, the Dow Jones Industrial Average fell 48.83 points (0.61 percent) to 7,948.45 after a 427-point slide Wednesday.

The tech-heavy Nasdaq dropped 5.80 points (0.42 percent) to 1,380.62 and the Standard & Poor's 500 index dipped 5.31 points (0.66 percent) to 801.27.

The latest economic news remained grim as the US Labor Department said new claims for unemployment benefits jumped to a 16-year high of 542,000.

Patrick O'Hare at Briefing.com said the mood on Wall Street remained cautious.

"The urgency to buy in the wake of yesterday's sell-off isn't there, most likely because investors have grown weary over the repeated failed rally attempts that have subsequently led to new lows," he said.

"Stocks could head lower still, yet the upshot is that, when that hopeless feeling hits, it typically means the market is close to a short-term bottom at least and that a meaningful move higher is in the offing."