New York, Feb 5 (DPA) US stocks posted their worst losses in nearly nine months Thursday as a surprising jump in weekly unemployment claims stoked fears that a jobless economic recovery has taken hold.

The sell-off erased major gains from the start of the week and came ahead of the US government's monthly unemployment report due out Friday morning.

New jobless claims in the US jumped to 480,000 last week, according to the Labour Department. The government is also expected to declare a massive revision Friday of the number of jobs lost during the country's two-year recession.

The Labour Department may have underestimated by nearly 1 million the number of jobs lost since the recession began in December 2007, raising the total to more than 8 million, US media reported.

Poor company earnings from MasterCard Inc and others also weighed on investors, while a 5-percent drop in the price of crude oil pushed down energy stocks.

European stocks had fallen earlier in the day on fresh concerns that Spain and Portugal were also facing dangerous budget deficits, one day after the European Union backed a plan for Greece to dig itself out of its own fiscal hole.

The Dow Jones Industrial Average plunged 268.37 points, or 2.61 percent, closing at 10,002.18. The broader Standard & Poor's 500 Index tumbled 34.17 points, or 3.11 percent, to 1,063.11. The technology-heavy Nasdaq Composite Index plummeted 65.48 points, or 2.99 percent, to 2,125.43.

The US currency climbed against the euro to 72.84 euro cents from 71.97 euro cents Wednesday. But the dollar tumbled against the Japanese currency to 88.95 yen from 91.01 yen a day earlier.