The British ministry of defence today faced calls to launch an official inquiry into a series of UFO sightings, including one filmed by a soldier on night patrol.

UFO experts believe the incidents, which happened in south Wales earlier this month, are 'particularly significant' because they included observations made by the crew of a police helicopter and military personnel.

The ministry confirmed today that it had been handed footage captured on a mobile phone by a corporal on guard duty at Tern Hill barracks, near Market Drayton, Shropshire, on 7 June.

Corporal Mark Proctor told The Sun newspaper that he witnessed a 'fleet' of objects zig-zagging across the sky at about 11pm.

The 38-year-old soldier, a member of the 1st Battalion Irish Regiment, said: 'I was on duty in the guard room when the other boys outside began shouting.

'I went out to see what the commotion was about and could see 13 craft in the skies. They were like rotating cubes with multiple colours.'

Former UFO expert at the British ministry of defence Nick Pope said that an inquiry to establish what had been seen by the witnesses was vital.

Mr Pope said: 'Something quite extraordinary does seem to be going on in British air space at the moment.

'There has got to be an official inquiry into all this and we need a senior air force officer to take personal charge and oversee the inquiry.'

Radar tapes, as well as footage of the incidents, should be examined as part of the investigation, said Mr Pope, who added: 'It's indisputable that something was seen - the very fact that it was seen by military personnel over a military base makes it a national security incident.'

A British army spokesman declined to comment in detail on the sightings at Tern Hill.

'The ministry examines reports solely to establish whether UK airspace may have been compromised by hostile or unauthorised military activity,' the spokesman said.

'Unless there is evidence of a potential threat, there is no attempt to identify the nature of each sighting reported.'