A HAMPSHIRE man will give evidence at the long-awaited second inquest into the death of a serviceman during nerve gas tests 51 years ago.

The hearing to learn more about the last moments of the life of Leading Aircraftman Ronald Maddison at Porton Down, the secret biological weapons research base on Salisbury Plain, began yesterday.

It was told that Winston Churchill's government attempted to keep details of the death of the 20-year-old secret due to "national security", with the first inquest held behind closed doors.

Mike Cox, now 70, of Devon Drive, Chandler's Ford, was sitting in a gas chamber next to LAC Maddison when he died.

He told the Daily Echo he had been asked to give evidence later this month after not being included in the original proceedings.

The initial brief inquest swiftly recorded a verdict of death by misadventure.

Yesterday's hearing was told that LAC Maddison had become the first person to die in trials at Porton Down and that all experiments then ceased, with Churchill informed of the decision.

Mr Cox, who attended the opening, said: "I was not called to the first inquest, we were kept in complete ignorance.

"I was very pleased when I heard there would be a new inquest.

"The coroner struck me as someone who was quite anxious to get to the truth of what happened.

"I am pretty confident the truth will come out - the truth has a habit of doing that."

Mr Cox, who was also subjected to experiments, said he had been in regular contact with the family of LAC Maddison in recent years.

The hearing in Wiltshire was told LAC Maddison was one of a team of six servicemen, including Mr Cox, who entered a chamber at Porton Down wearing respirators.

All were exposed to 200 milligrammes of Sarin, which was dropped on to a piece of uniform material loosely wrapped around their arms.

After 23 minutes however, LAC Maddison said he felt "pretty queer" and was taken outside where he began to experience breathing difficulties and was sweating.

He was given an antidote but his condition worsened and he said he couldn't hear.

He was taken by ambulance to the medical centre and given further treatments but slipped into unconsciousness and attempts to revive him failed.