Shortly after the 8.7-magnitude earthquake shook the Indonesian coast on Monday night, Sri Lankan meteorological officials informed of the quake by the US Geological Survey website rang the president's office, military top brass and police.

Within half an hour, Sri Lanka's radio and television stations interrupted normal programmes for an emergency message from the office of President Chandrika Kumaratunga, warning of a possible tsunami and urging coastal dwellers to seek higher ground.