Worries over China's relentless sell-off and Greece's debt crisis sent Asian equity markets into a tailspin on Wednesday.
The Shanghai Composite has fallen more than 30 percent from its mid-June peak amid frequent bouts of extreme volatility and analysts say the turbulence is starting to unnerve regional investors.
"China is a closed market so the impact is not so much on the global market, but we do see some impact spreading out, especially to Japan today, so that becomes a concern," Alex Wong, director of Asset Management at Ample Capital, told CNBC.
Meanwhile, the Greek government has until Friday morning to present detailed reform proposals to allow a bailout deal by a Sunday summit, according to a Reuters report citing two EU officials following the emergency euro zone summit in Brussels. Failure to reach a deal would make a "Grexit" - Greece's exit from the euro zone - more likely.
Overnight, U.S. stocks ended higher after a choppy session, as a rebound in U.S. oil prices helped offset concerns about China and Greece. The Dow Jones Industrial Average and S&P 500 closed up 0.5 and 0.6 percent, respectively, while the tech-heavy Nasdaq added 0.1 percent.
Mainland markets in free fall
It was another painful trading session in the world's second-largest economy, with the benchmark index closing down 6 percent following an 8 percent slide in early trade, after China's securities regulator warned of "panic sentiment."
Investors were also spooked by news that more companies have issued requests to suspend trading, including Hong Kong-listed China Jiuhao Health Industry and China Zenith Chemical.
Elsewhere in the mainland, the CSI 300 index and the Shenzhen Composite ended 6.7 and 2.5 percent lower after touching multi-month lows.
Hong Kong's Hang Seng index was not spared from the carnage; the index ended nearly 6 percent lower after tanking as much as 8 percent.
"For the Hang Seng, there is a contagion impact as many of the Chinese investors who went into A-shares also bought into the H-share market and by association, Hong Kong will rise and fall according to the fortunes of China," Wong Sui Jau, general manager at Fundsupermart.com, told CNBC's "Street Signs Asia." "However, while it is affected by the volatility, the downside should be a lot lesser than China because the valuations of H-shares remain much lower than A-shares."
Among losers, brokerages struggled to find a footing, with Citic Securities and Everbright sinking by the daily limit of 10 percent each in the mainland.
Most blue chips also fell, even amid fresh government support and news that government-backed investors are buying into financial heavyweights and oil giants. Bank of Communications receded 10 percent, while Sinopec and PetroChina lost 10 and 8.5 percent, respectively.
Nikkei loses 3.1%
Japan's Nikkei 225 crashed to a seven-week low as investors eyed the sell-off in China.
Companies with high exposure to the mainland were among the hardest-hit; Komatsu slumped 5.8 percent, while Hitachi Construction Machinery retreated 4 percent.
Other casualties included Itochu Corp, which sank 9.2 percent, after the Nikkei business daily reported that its plans to buy a stake in Bosideng International Holdings was rejected by the Chinese apparel company's shareholders.
Nissan Motor closed down 6.6 percent to its lowest level since February 20 following the company's announcement of an abnormal deployment of an airbag made by Takata.
On the domestic data front, Japan logged its eleventh straight monthly current account surplus in May, with the surplus widening to 1.88 trillion yen ($15.36 billion), topping a Reuters forecast for a 1.54 trillion yen surplus.
ASX tumbles 2%
Australia's S&P ASX 200 index gave up all of Tuesday's gains, with banks and miners leading the downward spiral.
Among the four major lenders, National Australia Bank, Australia and New Zealand Banking and Commonwealth Bank of Australia pulled back more than 2 percent each.
As commodity prices tanked on the back of worries over a deteriorating outlook in China, the resources sector succumbed to selling pressure, with Fortescue Metals losing 6.2 percent to hit its lowest level since January 2009. BHP Billiton and Rio Tinto also shaved off 3 percent each.
Meanwhile, Santos and Woodside Petroleum sagged 3.3 and 2.9 percent, respectively, in tandem with weaker crude oil prices.
In reaction to the mayhem in Chinese markets, the Australian dollar hit a fresh six-year low of $0.7397 against the greenback.
Kospi eases 1.2%
South Korea's Kospi index tracked regional weakness to finish at its lowest level since June 16, chalking up a four-session losing streak.
Pharmaceuticals were among the biggest laggards, with Daewoong Pharmaceutical and Hyundai Pharmaceutical easing 3.7 and 4.2 percent, respectively.
Mirae Asset Life Insurance declined 2.2 percent to 7,240 won per share in its market debut on Wednesday. The initial public offering (IPO) had priced below an indicative range of 8,200-10,000 won per share.
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Southeast Asian stocks eyed
Shares of Malaysian budget carrier AirAsia tanked more than 12 percent after Indonesia's transport ministry threatened to suspend the operating licence of its Indonesian affiliate unless the company raised new equity by end-July.
Meanwhile, Singapore Post closed 0.79 percent up to trade at 1.90 Singapore dollars, buoyed by news that Chinese e-commerce giant Alibaba Group plans to increase its equity stake in the Singapore-listed company. Following the news, OCBC held on to its 'buy' recommendation for the stock, with 2.19 Singapore dollars as a fair value estimate.