AN investigation was launched today into allegations that an Army instructor filmed recruits at a Hampshire barracks as they were forced to inhale CS gas.

A video obtained by the Sun newspaper shows soldiers apparently being placed into a sealed chamber while onlookers laugh and joke.

In the video, one recruit seems to become disorientated and throw up after breathing the gas.

The newspaper claims an instructor used his mobile phone to take the footage at the Army Training Regiment's base in Winchester.

A Ministry of Defence spokesman said that the Royal Military Police Special Investigation Branch would be investigating the two-and-a-half minute long video.

He added: "The Army takes all allegations of harassment and discrimination very seriously.

"Abuse leads to the erosion of discipline and team spirit, which are essential elements in operational scenarios."

A military source said recruits were routinely exposed to CS gas as part of their training.

"It's a requirement for pre-deployment training because of the risk of being gassed when on operations."

Soldiers are supposed to be exposed for around 20 seconds to improve their "tolerance" before passing the training, according to the source.