An Indian Air Force (IAF) helicopter Mi-17 V5 crashed on Friday in Tawang in Arunachal Pradesh on the India-China border, killing all seven people on board, an official said.
The chopper with five IAF and two Army personnel took off from Khirmu base.
A Defence Ministry official who wished not to be named told IANS that all the seven personnel were charred to death.
"The helicopter crashed at Tawang (500 metres of Yanse post). They were supposed to drop kerosene jerry cans. One of the jerry cans opened and entangled in tail rotor," the official said.
Earlier, Arunachal Pradesh Police chief Sandeep Goel told IANS that rescue teams from the Army, Indo-Tibetan Border Police and police had launched an operation to locate the chopper and to rescue those on board.
A Court of Inquiry has been ordered to establish what caused the crash.
In July, an IAF chopper engaged in a rescu mission during floods crashed near Papum Pare district in the hill state killing four persons including three IAF crew and one India Reserve Battalion (IRB) personnel.
In May, two IAF pilots in a Sukhoi-30 fighter jet crashed near the Assam-Arunachal border.
The frequently changing weather condition in Arunachal Pradesh makes flying of choppers difficult.