LONDON: Two British sailors were killed and a third injured in an accident on Wednesday on board a nuclear submarine under the ice cap in the Arctic Ocean, the Ministry of Defence (MoD) in London said.
Early indications were that the accident on board HMS Tireless involved a piece of air purification equipment to the bow (front) of the submarine, but the vessel was "never in any danger," the MoD said.
"The MoD can confirm that at (0430 GMT) this morning there was an accident onboard a Trafalgar Class submarine on exercise in the Arctic," it said.
"The submarine, HMS Tireless, was never in any danger, its nuclear reactor was unaffected, it quickly surfaced and is completely safe."
The hunter-killer submarine, which was taking part in a joint exercise with the US Navy, does not carry nuclear missiles.
The MoD said the family of the two crew members had been informed while the third who was injured was airlifted to a US military hospital.
His injuries are not thought to be life-threatening and he is expected to make a full recovery, it added.
"At this early stage, it is thought that the accident involved a piece of air purification equipment in the forward section of the submarine," the statement read.
"The ship's company dealt with the incident quickly and professionally and, as a result, there is only superficial damage to the forward compartment...
"The crew are trained in surfacing quickly through the ice, and did so in exemplary fashion."
