GUWAHATI, July 26: ULFA militants hiding in Nagaland have to ward off the security forces, waiting for them in Assam, and malaria, reportedly wreaking havoc in their camps. Two militants have already succumbed to the disease. Biplab Borthakur alias Amulya Barua, chief of ULFA's Dhansiri unit which looks after operations in Upper Assam, has died of malaria. Two unidentified persons brought his body to his Gorumora village home in Jorhat district this afternoon. A Jorhat police team later sent the body for autopsy. Ratul Dutta succumbed to malaria on 15 July on his way to the Assam Medical College and Hospital in Dibrugarh. The manager and doctor of Moabund tea estate have been arrested for allegedly treating Ratul at the garden hospital and the Mission Hospital in Jorhat. A district police official said a close watch is being kept on hospitals and nursing homes where the ailing militants may come for treatment. Some ultras have left their camps in Nagaland and are seeking shelter in villages in Assam. The official said this was the right time to raid ULFA camps as the sick militants would find it difficult to flee. They would also not put up any worthwhile resistance. But such action is impossible because of the declaration of ceasefire in Nagaland. Any operation could create complications. The militants are not the only ones to be threatened by malaria, which claims 800 to 1000 lives annually in the Northeast. Security forces in the region, large parts of which fall in the tropical malaria zone, are badly hit as well. A study says 20 CRPF jawans died of the disease last year. The death rate (0.31 per cent) is considerably high. The study says the troops are prone to malarial attacks because of their mobility, which affects personal protection measures and the body's immune system. Ultras kill two: Suspected Dima Halam Daoga militants shot dead two persons and injured six others at Herengajao village, 40 km from Haflong in the North Cachar Hills district, this morning. Information available here said the ultras fired indiscriminately at shoppers at the weekly market. The injured have been admitted to the Haflong Civil Hospital where the condition of three persons is reportedly critical.