U.S. import prices fell 0.4 percent in March on declines in natural-gas and petroleum prices, and new claims for jobless benefits rose by an unexpectedly large 12,000 last week, the Labor Department said Thursday in two separate reports. The larger-than-expected decline in import prices was the third in four months and followed a 0.5 percent drop in February. For the 12 months ending in March, import prices rose 4.5 percent, significantly slower than the 7.2 percent rise recorded in the 12 months ending in February. Oil prices were the chief driver of the 12-month increase, although such prices have been volatile. Petroleum import prices fell 0.7 percent in March but are up 22.6 percent over the past 12 months. Non-petroleum import prices fell 0.3 percent last month and are up a mild 1.1 percent in the last 12 months. An 11.9 percent drop in natural-gas prices last month was the main factor behind March's decline, more than offsetting higher metals prices, which rose 3.2 percent last month and have risen 31.8 percent in the past 12 months. Export prices rose 0.2 percent in March. The Federal Reserve closely watches import prices for signs of inflation, as companies may try to raise the costs of their goods to offset higher prices paid for raw materials. In a second report, the Labor Department said first-time claims for jobless benefits rose to 313,000 last week from 301,000 the previous week. The four-week moving average of new jobless claims, which smoothes volatile weekly data to offer a better picture of underlying labor market trends, fell by 1,500 last week to 307,750. A department official said there were no special factors affecting the data, and the labor market continues to show strong conditions. In another sign of a strong job market, the number of Americans who continued to collect jobless benefits fell by 4,000 to 2.424 million, bringing so-called continued jobless claims to the lowest level since late January 2001.