A tsunami warning was issued following a 7.5-magnitude earthquake that struck 150 km south of Papua New Guinea on Tuesday.According to the US Geological Survey, the epicentre, with a depth of 10.0 km, was initially determined to be at 5.6 degrees south latitude and 152.1 degrees east longitude.It issued a "hazardous" alert within 300 km of the epicentre, Xinhua news agency reported.Islands in Papua New Guinea, Solomon Islands, Indonesia, Vanuatu, Fiji, Indonesia, the Philippines and surrounding nations are expected to be hit by the strong waves.However, no casualty or damage to property was reported.