While two MI-17 choppers took off from Tawang this morning, two Cheetah and Chetak choppers flew from Tezpur in search of the missing copter as search operations entered the fifth day, defence sources in Tezpur said.
About 3000 personnel from the Army, SSB, ITBP, NDRF (National Disaster Response Force) along with the state police and local people resumed massive ground search operations at the break of dawn in five probable locations including Putujiji area under Bhutan, Dirang-based ITBP commandant Awanish said.
"The rescue teams are focussing on eastern Bhutan, basically on a grazing ground along with four other locations in West Kameng district near Sela Pass", he said.
The ground search parties are facing problems because of inaccessible and hostile mountainous terrain in an altitude of 13,000 feet above sea level, he said.
Local leaders of Tawang and its adjoining areas have urged the state government to take help from NASA in tracing Khandu.
Several NGOs and people have urged the Centre to contact neighbouring China for assistance to trace the missing chopper.
The single engine four-seater Pawan Hans helicopter with Dorjee and four others on board went missing soon after taking off from Tawang on Saturday.
The state government yesterday announced a cash reward of Rs 10 lakh for information on the missing helicopter.
Tawang Cultural Society, a NGO based at Tawang, also announced a cash award of Rs 5 lakh to any person who could provide clues on the whereabouts of the chopper.