WASHINGTON (MarketWatch) - New applications for unemployment benefits sank by 37,000 last week to 391,000 to mark the lowest level since April, but a government official suggested the surprising drop may have stemmed from a variety of "technical" issues not captured by normal seasonal adjustments. Initial claims from two weeks ago were revised up to 428,000 from an original reading of 423,000, the Labor Department said. Economists surveyed by MarketWatch had expected new claims in the week ended Sept. 24 to fall to 417,000 on a seasonally adjusted basis. The average of new claims over the past four weeks, meanwhile, fell by 5,250 to 417,000. The number of Americans who continue to receive regular state unemployment checks declined by 20,000 to 3.73 million in the week ended Sept. 17. About 6.98 million people received some kind of state or federal benefit in the week of Sept. 10, up 95,242 from the prior week.