A ROYAL Navy officer shot dead on board a nuclear-powered submarine in Southampton has been formally named by the Ministry of Defence as Lieutenant Commander Ian Molyneux.

He was killed on board HMS Astute yesterday when another member of the crew opened fire with a SA80 assault rifle.

Lt Cmdr Molyneux was 36 and from Wigan.

His wife Gillian Molyneux, said: ''Ian was utterly devoted to his family.

''Everything he did was for us. He was very proud to be an officer in the Royal Navy Submarine Service. He will live on in our four beautiful children.''

It has also been confirmed that a second man injured in the shooting was Lt Cmdr Chris Hodge.

He is said to be conscious in hospital today where his condition was described as stable.

Southampton's top policeman, Chief Superintendent Dave Thomas said this afternoon officers have been granted a warrant by Southampton magistrates to continue questioning the suspect.

He did not confirm the identity of the arrested man, who has been named unofficially as Able Seaman Ryan Donovan, 22.

Ch Supt Thomas said officers have so far questioned 20 witnesses about the shooting.

He said: "The full circumstances leading to this incident are yet to be established.

"However, at no time was the submarine's security breached, or the vesel's nuclear safety compromised, and as such there was no threat to public safety.

"HMS Astute remains a crime scene, and as such the constabulary has yet to release her back to the Ministry of Defence.

"Hampshire Constabulary's major crime department continue to investigate this matter with the support and cooperation of the Ministry of Defence police and Navy police."

• Fatal shooting on nuclear sub
• What it's like on HMS Astute
• HMS Astute factfile
• Southampton sub chief relieved of command
• Stricken sub commander from Southampton
• HMS Astute to visit Hampshire