Seven persons have been killed and several others injured in an attack on a madrasa at a Rohingya camp in Bangladesh's Ukhiya upazila of Cox's Bazar district, officials said.The deceased have been identified as Hafez Md. Idris, 32, Ibrahim Hossain, 24, Azizul Haque, 22, and Md. Amin, 32, Madrasa teachers Nur Alam, Hamidullah, 55, and another student Nur Kaiser, 15 . The militants on Friday attacked Darul Ulum Nadwatul Ulama Al-Islamia Madrasa, 8th APBN deputy captain Kamran Hossain told IANS.Among the injured, three died on the way to hospital, he said, adding that a person named Mujib was detained in this connection.