NEW DELHI, Nov. 30 (Xinhua) -- At least three Indian Army officers have been killed and one injured in a helicopter crash in the eastern Indian state of West Bengal Wednesday, a defense official said.

"The crash took place when the Cheetah helicopter of the Indian Army, which was on a routine sortie, was about to land at Sukhna military base in West Bengal a little after 10.30 a.m. (local time)," he said, on condition of anonymity.

Soon after the incident, senior Indian Army officials and a rescue team rushed to the spot, he said, adding the injured has been admitted to a local hospital where his condition is said to be serious.

A court of inquiry has been ordered by the Indian Army into the crash, the official said.

The Sukhna military base is home to Indian Army's 33 Corps and the chopper was operated by the Army Aviation Corps.

In the forces, since the 1960s, the state-owned Hindustan Aeronautics Limited built the single-engine Cheetah (original model SA 315B Lama) under licence from French state-owned firm Aerospatiale. There are a little over 100 such choppers with the Indian military.