All that separates northern Malaysia and southern Thailand here is a meandering ribbon of dun-colored water. Men with wiry bodies ply the river in wooden boats dozens of times a day, smuggling bags of Thai rice or Malaysian flour, and ferrying women in head scarves and men in Muslim caps on the five-minute trip across the water to shop or visit relatives. Border guards are few. It is here, said an intelligence official from the region, that a key Indonesian al Qaeda operative named Riduan Isamuddin, known as Hambali, crossed from Malaysia into Thailand in January 2002. Then, in February, Hambali, Southeast Asia’s most-wanted Islamic militant, went to the Thai capital, Bangkok, Indonesian police said. There, according to terrorism analysts, he convened a meeting of al Qaeda operatives at which he discussed a tactical shift in operations in the region. Full Story