KHAO LAK, Thailand (AP) — Beachside memorials and religious services were planned across Asia on Friday to mark the 10th anniversary of the Indian Ocean tsunami that left more than a quarter million people dead in one of modern history's worst natural disasters. The disaster was triggered by a 9.1-magnitude earthquake, the region's most powerful in 40 years, that tore open the seabed bed off of Indonesia's Sumatran coast, displacing billions of tons of water and sending waves roaring across the Indian Ocean at jetliner speeds as far away as East Africa. The sea rose as high as 10 meters (33 feet) and surged inland for kilometers (miles) with seemingly unstoppable force, carrying along trees, houses, train cars — and thousands of people — in a churning rush.