The number of unemployed U.S. workers claiming an initial week of jobless aid unexpectedly rose last week by 7,000, taking a four-week average of claims to the highest level since October, the government said on Thursday.

First-time claims for state unemployment benefits increased to a seasonally adjusted 336,000 in the week ended May 27, the Labor Department said. The increase was at odds with Wall Street forecasts for a drop to 320,000.

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The four-week moving average of claims, which smooths weekly fluctuations to provide a better picture of labor-market trends, climbed to 333,500. That was its highest level since late October, when claims were elevated due to hurricane damage along the U.S. Gulf Coast.

A Labor Department analyst said there were no special factors to account for last week's rise in claims.

The number of people who continued to file for benefits after receiving an initial week of aid rose by 19,000 to 2.43 million in the week ended May 20, the latest for which figures are available. However, a four-week moving average of that labor-market barometer hit its lowest level since January 2001.

The claims data comes one day ahead of the department's May employment report, which will be closely parsed for clues on the direction of the U.S. economy and interest rates. Economists expect 175,000 new jobs were added to nonfarm payrolls last month, a bit of a bounce back from the relatively soft 138,000 positions created in April.

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