MANILA - A powerful blast killed at least five people and wounded three near a school on a southern island in the Philippines on Thursday, a marine general said. No has claimed responsibility for the attack but a small band of Islamist militants with close ties to al Qaida and regional network Jemaah Islamiah (JI) operates on the island, Brigadier General Romeo Tanalgo, marine commander, said. Since 2004, a small group of U.S. soldiers is based on the island in the south of the mainly Roman Catholic state, helping train local soldiers fight Islamist militants.