HONG KONG: Hong Kong stocks tumbled more than three percent Tuesday morning over fears about a possible Russia-Ukraine war and as tech firms were hit by fresh concerns of a crackdown by China.

Equity markets across Asia have been sent tumbling after Russian President Vladimir Putin sent troops into two separatist regions in eastern Ukraine, ramping up geopolitical tensions and fears of a conflict.

The move came hours after the Kremlin appeared to pour cold water on a potential summit with US President Joe Biden and led to condemnation from world leaders and warnings Moscow would be hit with a series of sanctions.

The news added to an already dour mood in Hong Kong, where tech firms were hit by concerns Beijing will resume its crackdown on the sector following a report that regulators had ordered a probe into state firms' links with Alibaba fintech arm Ant Group.

Stocks skid, oil pops as Ukraine crisis deepens

The Hang Seng Index dived more than three percent at one point but made a marginal recovery to end the day down 2.69 percent, or 650.07 points, at 23,520.00.

The Shanghai Composite Index shed 0.96 percent, or 33.47 points to 3,457.15, while the Shenzhen Composite Index on China's second exchange lost 1.23 percent, or 28.50 points, to 2,297.30.

China's biggest state-owned firms and banks were told to begin a new round of checks on their financial exposure and other links to Ant and its subsidiaries, Bloomberg News said.

Mainland authorities have since 2020 embarked on a wide-ranging crackdown on alleged anti-competitive practices by Alibaba and other domestic tech giants.

The Hang Seng Tech Index closed 1.89 percent off, with market heavyweight Alibaba down more than three percent, while food delivery firm Meituan lost more than five percent.