Asian stocks fell on Wednesday after Iran attacked several U.S. military bases in Iraq in retaliation to the U.S. killing of Quds Force Commander Soleimani last week.
"Iran took & concluded proportionate measures in self-defense," Foreign Minister Javad Zarif announced on Twitter. "We do not seek escalation or war, but will defend ourselves against any aggression."
Iraq's military said it had no troop casualties in the Iranian strike, while U.S. President Donald Trump tweeted that "All is well!".
China's Shanghai Composite index fell 37.91 points, or 1.22 percent, to 3,066.89 while Hong Kong's Hang Seng index dropped 0.83 percent to 28,087.92.
Japanese stocks ended sharply lower and the yen turned volatile after Iranian forces launched a barrage of more than a dozen ballistic missiles against two Iraqi military bases that house American and coalition forces.
The Nikkei index briefly fell over 600 points to below the 23,000 line for the first time since November before recovering some lost ground to end the session down 370.96 points, or 1.57 percent, at 23,204.76. The broader Topix index closed 1.37 percent lower at 1,701.40.
Heavyweights Fast Retailing and Fanuc ended down around 2 percent while SoftBank Group dropped 1.4 percent. Shipping firm Kawasaki Kisen Kaisha plunged 5.9 percent, while property developer Tokyu Fudosan Holdings Corp and chemicals maker Tosoh Corp lost around 4 percent.
Australian shares recovered from steep losses to end the session on a flat note. The benchmark S&P/ASX 200 ended down 0.13 percent at 6,817.60 after falling around 1 percent earlier in the session following news of an Iranian missile strike on U.S. and Iraqi air bases in Iraq. The broader All Ordinaries index edged down 0.19 percent to close at 6,930.10.
Tech stocks Appen and Wisetech Global fell more than 3 percent. Mining heavyweight Rio Tinto shed 0.9 percent and Fortescue Metals Group dropped half a percent. The big four banks fell between 0.3 percent and 0.4 percent.
Sigma Healthcare declined 0.9 percent as chief financial officer Iona MacPherson resigned amid the company's ongoing restructuring program.
Energy stocks continued to rise, with Beach Energy, Woodside Petroleum and Santos ending up over 1 percent. Gold miner Evolution Mining rallied 2.1 percent and Newcrest surged 4 percent as gold prices started a new bull run.
In economic releases, the day's reports on housing and construction activity proved to be a mixed bag.
Seoul stocks tumbled amid concerns that escalating tensions in the Middle East may push up global oil prices. The benchmark Kospi fell 24.23 points, or 1.11 percent, to 2,151.31 on heavy volume.
Top refiner SK Innovation plunged 5.2 percent and chemical firm LG Chem declined 2.9 percent. Automaker Hyundai Motor gave up 3 percent and its affiliate Kia Motors shed 1.8 percent.
Market heavyweight Samsung Electronics gained 1.8 percent after it flagged a smaller-than-expected fall in quarterly operating profit. SK Hynix shares surged as much as 3.6 percent.
New Zealand shares fell notably, with the benchmark NZX-50 index ending down 72.88 points, or 0.63 percent, at 11,556.98. Exporter Fisher & Paykel Healthcare lost 2.6 percent.