The nuclear submarine on which two crew members died in Arctic waters yesterday has a history of high-profile incidents.

In its 23-year history, the Trafalgar Class submarine, based at Devonport in Plymouth, has been in a collision, has been taken out of service for repairs and has sparked an international anti-nuclear protest.

In 2000, all similar vessels were inspected after the Tireless suffered a leak in pipework while on operations between Sicily and North Africa. A coolant escape in the reactor department forced the crew to take the submarine to dock in Gibraltar on back-up diesel engines.

HMS Tireless had to remain in dock for almost a year while repairs were carried out. It became the focus of protests by Spanish anti-nuclear campaigners, thousands of whom marched through the streets, amid fears of radioactive leaks into coastal waters.

An intensive inspection programme on the rest of the 12-strong UK hunter-killer fleet was carried out. Less than a year earlier, Tireless had returned to operations after a three-year refit.

Seven Trafalgar Class subs and five Swiftsure vessels were docked while the possibility of a generic failure in the cooling system was examined. The inspections left the UK with a diminished fleet and only one attack submarine was on patrol.

Tireless returned to home waters but she was involved in another incident, this time colliding with an object while submerged in 2003.

In that incident, she suffered minor damage to a ballast tank when she hit what is thought to have been an iceberg, again while on an operation in the Arctic.

The 5200 tonne submarine is the third of seven Trafalgar Class SSN submarines in the Royal Navy and carries a crew of 130.

The atmosphere onboard is constantly monitored. An electrolyser produces oxygen and absorbers remove gases such as carbon dioxide.