THE Ministry of Defence last night mounted a major investigation after an RAF Tornado crashed just miles from Torness nuclear power station, near Dunbar, East Lothian.

Aviation experts were attempting to unravel the incident which resulted in the pilot and his navigator losing control of the F3 Fighter in a no-fly zone around the station.

An MoD spokesman said last night that there was no direct threat to nuclear safety as the craft, which was on a training exercise from Coningsby in Lincolnshire, ditched into the North Sea two miles south of the power station.

The crew, who were on a top-level training mission involving intercepting bombs at high-altitude, used their ejector seats and parachuted on to the shore. They managed to walk to a nearby farm house where they telephoned base and were flown to Edinburgh Royal Infirmary last night for check-ups.

An MoD spokesman said: ''The men are safe and unharmed. They phoned base to say they were alive and well and there were no civilian casualties.

''We have no idea what happened and we are obviously keen to speak to the pilots concerned. We do know that the craft landed in the sea some miles from the station.''

However, the incident is the latest in a string of accidents involving Tornado jets. In January, four people were killed when an RAF Tornado collided with a Cessna light aircraft near a school in a village outside Worksop in Nottinghamshire.

Last month, an RAF pilot was killed when his Hawk plane crashed near a main London to Scotland railway line and, earlier in October, an RAF pilot was rescued from the Moray Firth after his Jaguar crashed.

A spokeswoman for British Energy said last night that there was a recognised no-fly zone around Torness, but it was premature to say what had happened.

She added: ''At this early stage, we do not know why the craft was in this area, that is a matter for the RAF, but we have systems in place for such incidents and we are confident there was no threat to safety.''

Two rescue helicopters from RAF Boulmer in Northumberland and HMS Gannet near Prestwick were scrambled in the operation after the craft ditched just after 6pm last night. The RNLI at Dunbar launched rescue boats as initial reports suggested the men had gone down with the craft.

A spokesman for the RAF said last night: ''We can confirm a Tornado crashed at around 6.20pm. The crew are being taken to a medical facility. We believe they are okay but it is up to medical staff to assess their condition. The aircraft crashed to sea but the crew landed on land.''

The spokesman said it was too early to comment on the cause of the accident. He added: ''As far as we are aware, there was no indication it was going to happen and we do not know why it happened.''