UNB, Netrakona : Three madrasah students were killed as a streak of lightning struck them at Ghagra in Purbadhala upazila on Sunday night.The deceased were identified as Masum, 15, a resident of Agia village, Rafat, 15, of Giriasha village,and Masum, 15, of Ghagra Charpara village. All of them are students of Ghagra Chourasta Fazil Madrasah.Officer-in-Charge of Purbadhala Police Station Abdur Rahman said the trio was struck by the thunderbolt around 9pm as they went out of the dormitory of their madrasah to respond to the call of nature, leaving them dead on the spot.