Nikkei tumbles 5.2% to five-week low

Extends the benchmark's losses to more than 14% since last Thursday's plunge

The Nikkei share average dived to a five-week low on Thursday as the yen firmed further against the dollar, triggering a market-wide selloff, and extending the benchmark's losses to well over 14% since last Thursday's plunge.

The benchmark Nikkei fell 5.2% to 13,589.03, the lowest since April 22. The latest decline has pulled the Nikkei 14.8% below the 5-1/2-year high reached last week.

The broader Topix index dropped 3.8% to 1,134.42.