BEIJING, Dec. 28 (Xinhua) -- China's Ministry of Information Industry and major telecom operators have started an emergency action to detect the damages caused by a powerful earthquake off the Taiwan coast on undersea fibre-optic cables. 

    The Ministry said China Telecom and China Netcom were taking active measures to repair the damaged cables which had interrupted the Internet connection services from the Chinese mainland to North America, Europe, Singapore and the Asia-Pacific areas.

    The ministry didn't say when normal service would be restored.

    China Telecom, the mainland's largest fixed-line carrier, said six undersea cables were cut off 15 kilometers from the southern coast of Taiwan, causing severe Internet congestion on the mainland.

    The quake, which hit late on Tuesday just offshore from the Pingtung County township of Hengchun, came on the second anniversary of the devastating tsunami that took more than 200,000 lives in southern and southeastern Asia.

    The earthquake measured 7.2 on the Richter scale, according to the Hong Kong Observatory. Its epicenter was initially determined to be over Luzon Strait (21.8 north latitude, 120.6 east longitude), about 97 kilometers south-southeast of Kaohsiung.