Seven mountaineers, including two who have scaled Mount Everest, on Sunday joined the search for the AN 32 aircraft that went missing in Arunachal Pradesh after taking off from Jorhat in Assam on June 3, reported the Hindustan Times. The Indian Air Force has undertaken a massive search operation to trace the plane, but there has been no breakthrough yet.

The transporter aircraft, with 13 people on board, went missing 33 minutes after taking off from Jorhat. It was heading to Menchuka in Arunachal Pradesh, near the China border.

“They left today [Sunday] at six in the morning,” Siang Superintendent of Police Kushal Pal Singh told the Hindustan Times. Taka Tamut and Kishon Tekseng, who scaled Mount Everest in 2018, are both from Arunachal Pradesh and are well versed with the region’s topography, said an unidentified official. The five other members of the team have also undergone a course in adventure tourism.

The aircraft is suspected to have disappeared either in Payum Circle or Kaying Circle in Siang district. The mountaineers have been sent along with other ground teams to the jungles in Payum Circle. “It is a very thick jungle where the aircraft is suspected to have been lost,” said Singh.

The Air Force, Navy, Army, local police, state government, paramilitary forces and the local residents are involved in the search operation. The Indian Air Force has deployed helicopters, transport aircraft, Unmanned Aerial Vehicles and other sensors, along with Navy’s P8I aircraft. Electronic, radar, optical and infrared sensors, including satellites, have also been used to scan the area. The Indian Air Force has announced a cash reward of Rs 5 lakh for information on the missing plane.