TORONTO — North American stocks hit session lows in early afternoon trading on Thursday, with the S&P 500 on track to post its worst day in six weeks, as tension over Ukraine’s Crimean peninsula mounted.The Dow Jones industrial average fell 177.34 points or 1.09%, to 16,162.74, the S&P 500 lost 17.54 points or 0.94%, to 1,850.66 and the Nasdaq Composite dropped 57.698 points or 1.33%, to 4,265.634.Ukraine’s acting president said Russian forces were concentrated on the border “ready to invade” his country but he believed international efforts could end Moscow’s aggression and avert the risk of war.The Toronto stock market was also lower, declining 68 points to 14,250.Worries about the pace of Chinese growth also weighed on stocks. Industrial production in the country rose by a lower than anticipated 8.6% in the first two months of this year.Also, China’s premier Li Keqiang said that his country will keep this year’s economic expansion strong enough to create new jobs but will emphasize market-opening reform and the environment over hitting its official growth target of 7.5%.“So, the Wild East is over now, and they’re moving to a more managed scenario, they’re going to tighten the screws,” said Wes Mills, chief investment officer Scotia Private Client Group.“And sure, it’s a slower growth, more micromanaged kind of environment and in the long run, it’s good, in the short run, it’s got the commodity guys nervous.”Copper added to its recent losses on the dimmer outlook for China, which accounts for 40 percent of global refined copper demand. The metal hit a four-year low at $6,376.25 per tonne on Wednesday.© Thomson Reuters 2014 read more