LONDON -- A British Royal Navy sailor has been arrested after he shot dead one colleague and left another with life threatening injuries following an incident Friday aboard a nuclear-powered submarine docked in a southern English port.

Britain's Defense Secretary Liam Fox said he was saddened by the "tragic incident" which took place on the nuclear-powered HMS Astute while it was docked in the city of Southampton.

Police said officers were attempting to contact relatives of the dead and injured servicemen following the shooting, which took place at around 11:10 a.m. local time.

"Two Royal Navy personnel have been involved in a firearms incident at Southampton docks," Britain's defense ministry said in a statement. "Sadly, one has now died as a result of his injuries."

The ministry confirmed that the incident was not terrorism related.

Three local dignitaries were also aboard the ship at the time of the shooting, but were unharmed.

"I am greatly saddened to hear of this incident and of the death of a Royal Navy service person in this tragic incident. It is right and proper that a full police investigation is carried out," Fox said.

Southampton City Council said the council's leader Royston Smith, city mayor Carol Cunio and chief executive Alistair Neill were touring the $1.6 billion vessel at the time of the shooting.

"We can confirm they are safe and unharmed and should be coming off and taken away by car soon. They have clearly been through a traumatic experience," the council said in a statement.

The Astute ran aground in late October after hitting rocks off the Isle of Skye off the west coast of Scotland. It was stuck for several hours until it was towed to safety.

One of Britain's fleet of 11 submarines powered by nuclear reactors, it was launched in 2007 and is armed with Spearfish torpedoes and Tomahawk cruise missile.

The defense ministry said it planned to open a Royal Navy investigation into the shooting.

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