TOKYO, April 11 (Reuters) - Japanese shares tumbled to six-month lows on Friday and posted their biggest weekly fall since the March 2011 tsunami and nuclear disaster after a rout in U.S. tech shares spurred selling by momentum players.
The Nikkei fell 2.4 percent on the day to 13,960.05, the lowest finish since Oct. 8 and down 7.3 percent on the week. It was the biggest weekly fall since the week following the earthquake in March 2011, when the Nikkei fell 10.2 percent.
Fast Retailing, the Nikkei heavyweight and casual clothing giant, sank after it cut its full-year operating profit forecast at a time when investors were already nervous about fallout from a sales tax hike.
While the Nikkei was dragged down by Fast Retailing and another Nikkei heavyweight SoftBank, the broader Topix index fell 1.3 percent and the new JPX-Nikkei Index 400 dropped 1.4 percent.
(Reporting by Hideyuki Sano; Editing by Eric Meijer)