Tokyo - Tokyo stocks fell on Monday morning as the yen jumped in response to North Korea firing four ballistic missiles, three of which landed in Japanese-controlled waters.
Japanese Prime Minister Shinzo Abe said the missiles were launched "almost simultaneously" and warned the threat from Pyongyang had "entered a new stage".
"Investors seem to be reacting to the North Korean missile launch," said Hiroaki Hiwada, a strategist at Tokyo Securities.
"The yen's strengthening and investors are staying away from trades as geopolitical risk increases.
I do think this is a temporary situation as we've seen in the past, but with this many missiles being launched there's heightened tension," he told Bloomberg News.
The Nikkei 225 index fell 98.70 points, to 19 370.47 by the lunch break, while the Topix index of all first-section issues was down 4.32 points, to sit at 1 553.73.
In Asian forex markets, the dollar slipped to ¥113.84 on Monday from ¥114.05 in New York on Friday afternoon.
A rise in the yen, which investors often buy as a safe investment during times of uncertainty and turmoil, is bad for the profitability of Japan's exporters and hits demand for their shares.
Toyota fell 0.30% to ¥6 435 while Sony lost 0.99% to end the morning at ¥3 566.
Banks were also lower, with Mitsubishi UFJ Financial dropping 0.30% to ¥756.2.
Yamato Holdings dropped 4.60% to ¥2 426 on reports that the major delivery firm would retroactively compensate its parcel carriers for unpaid overtime totalling tens of billions of yen (hundreds of millions of dollars).
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