New claims for U.S. jobless aid rose an unexpectedly large 12,000 last week, government data showed on Thursday, but underlying measures of the labor market continued to show robust conditions.

First-time claims for state unemployment insurance benefits advanced to 313,000 in the week ended April 8, compared with an upwardly revised 301,000 the prior week, the Labor Department said.

Wall Street analysts polled by Reuters had expected 300,000 new claims, up from an initially reported 299,000 the prior week. A Labor Department official said there were no special factors affecting the data.

The four-week moving average of new claims, which smooths volatile weekly data to offer a better picture of underlying labor market trends, shrank by 1,500 last week to 307,500.

In another sign of a buoyant U.S. employment situation, the number of people who continued to collect jobless benefits after drawing an initial week of aid decreased by 4,000 to 2.424 million in the week ended April 1, the latest period for which these figures are available.

The fall, compared with a forecast for 2.453 million, took so-called continued claims to the lowest level since Jan. 20, 2001, when they came in at 2.419 million.

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