Thousands of Sri Lankan troops have launched a massive operation to rescue nearly a million people affected by floods in the central, north and eastern provinces. The flooding has killed at least 13 people, officials said. More than 28,000 troops, backed by transport helicopters and navy boats, are rescuing flood victims and delivering food, authorities said. It is the biggest troops operation since the defeat of Tamil Tiger rebels one-and-a-half years ago. Authorities are making arrangements to take baby food, mosquito repellents and medical supplies to the area.