Midday Report: Biogen to Spinoff Hemophilia Unit; U.S. Stocks Slump

U.S. stocks extended losses after fears spiked China's economy could be in trouble on Tuesday. Factory activity in the world's second largest economy remained in contraction territory for its 14th month in a row in April. Automakers appeared to rebound from weakness in March, though record levels achieved last year made for tough comparisons. Ford (F) - Get Report sales rose, though at a far weaker pace, and General Motors (GM) - Get Report reported a steeper-than-expected decline. Meanwhile, Fiat Chrysler (FCAU) - Get Report blew them both away after reporting its strongest April in 11 years. Aeropostale (AROP) tumbled on reports it is preparing to file for Chapter 11 bankruptcy protection this week. TheStreet's Keris Lahiff reports from Wall Street.