A major 7.5-magnitude earthquake hit off the coast of the South Pacific island of Vanuatu early today. The US Geological Survey said the quake struck at 3:55 am local time at a depth of 40 kilometres, around 60 kilometres south of Port Vila, the capital of the island nation. The seismologists also detected a second smaller 5.9-magnitude tremor minutes after the first quake. However, no tsunami warning was issued and there was no immediate reports of damage.