Business Roundup for Thursday, March 13.

Traders work on the floor of the New York Stock Exchange (Spencer Platt/Getty Images)

NEW YORK (AP) — Stocks are closing sharply lower as tensions flare up over Russia's presence in Ukraine. The Dow Jones industrial average fell 231 points, or 1.4 percent, to close at 16,108 Thursday, its worst loss in six weeks. The Standard & Poor's 500 index fell 21 points, or 1.2 percent, to 1,846. The Nasdaq composite fell 62 points, or 1.5 percent, to 4,260. U.S. and European leaders have been stepping up their rhetoric against Moscow ahead of a weekend vote in Crimea over whether to secede from Ukraine and join Russia. Secretary of State John Kerry warned Russia that it will face "very serious" steps from the U.S. and Europe if it annexes Crimea. Bond prices rose as traders sought safety. The yield on the 10-year Treasury note fell to 2.65 percent.

SIMFEROPOL, Ukraine (AP) — There's a run on banks in Ukraine's Crimean Peninsula. Customers have been lining up to withdraw cash from their accounts ahead of Sunday's referendum on joining Russia. Ukraine's largest bank says it's imposed a $150 limit on daily withdrawals across the entire country, as banks in Crimea struggle to deliver cash to customers.

WASHINGTON (AP) — Three nominees for the Federal Reserve's board are expressing their support for the Fed's efforts to bolster the U.S. economy. Stanley Fischer has been nominated to be vice chairman. In a Senate confirmation hearing today, Fischer noted that the Fed is trimming back its stimulus effort but will need to continue an "expansionary monetary policy" for the economy to reach maximum employment and price stability.

WASHINGTON (AP) — Mortgage rates continue to edge higher, though they remain close to historically low levels. Mortgage buyer Freddie Mac says the average rate for a 30-year fixed loan increased nearly a tenth of a point to 4.37 percent last week. The average for a 15-year fixed mortgage rose to 3.38 percent. Mortgage rates have risen about a full percentage point since hitting record lows roughly a year ago.

WASHINGTON (AP) — The government wants commercial trucks and buses that cross state lines to be equipped with electronic devices that record how many hours the vehicles are in operation. The Federal Motor Carrier Safety Administration's proposal is intended to prevent drivers from exceeding limits on the number of hours they can spend behind the wheel. Accident investigators have pointed to crashes where drivers regularly were exceeding limits on work hours, sometimes fiddling with log books to cover it up.

WASHINGTON (AP) — There's a fresh sign that the job market is picking up after a winter slump. First-time claims for unemployment benefits dropped 9,000 last week to a seasonally adjusted 315,000. The Labor Department also says the four-week average of applications fell to 330,500, the lowest since early December.

WASHINGTON (AP) — Retail sales bounced back in February after suffering a steep decline during a bitterly cold January. Shoppers spent more on autos, clothing and furniture. The Commerce Department says seasonally-adjusted retail sales rose 0.3 percent in February. That followed drops of 0.6 percent in January and 0.3 percent in December.

WASHINGTON (AP) — U.S. businesses continued to restock their shelves and warehouses in January, despite plunging sales. The Commerce Department says inventories rose 0.4 percent, while sales dropped 0.9 percent in January. The report suggests that winter weather kept shoppers at home, but businesses anticipate a rebound.

LOS ANGELES (AP) — Americans spent an all-time high of $55.7 billion on their pets last year. That was an all-time high, and the American Pet Products Association says it expects spending to reach close to $60 billion this year. Pet food accounted for more than a third of the spending.

SEOUL, South Korea (AP) — International stock markets are mixed today with resurfaced concerns about China's economy after lackluster factory production and other data. Benchmark U.S. crude oil fell below $98 a barrel. The dollar fell against the euro and the yen.

BEIJING (AP) — China's premier says the country will keep this year's economic expansion strong enough to create new jobs but will emphasize market-opening reform and cleaning up smog-choked cities over hitting its official growth target. Li Keqiang's comments today reinforced the ruling Communist Party's pledge to shift to cleaner, more sustainable growth based on domestic consumption and service industries instead of trade and investment.

TOKYO (AP) — Air pollution in China is going to mean a financial benefit to some Panasonic employees living there. The Japanese electronics maker is making the payment part of a package negotiated annually for employees in China who belong to the Panasonic union. Panasonic says the compensation is not offered to locally hired staff.

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