Nikkei falls 4 pct hit by firmer yen, oil

TOKYO, Jan 4 (Reuters) - Japan's Nikkei average tumbled more than 4 percent on Friday, the first trading day for a week, hitting its lowest close since July 2006, while the broader TOPIX index marked its lowest close since October 2005.

Exporters were battered by a combination of a stronger yen, high oil prices and growing worries about the U.S. economy, with high-tech firms such as Sony Corp (6758.T) hit especially hard. In a half day of trading, the benchmark Nikkei .N225 closed down 4.03 percent, shedding 616.37 points to finish at 14,691.41 for its biggest daily percentage loss since Aug. 17, 2007. It had earlier fallen more than 5 percent to 14,542.58. The TOPIX closed down 4.3 percent at 1,411.91, a loss of 63.77 points. (Reporting by Elaine Lies)