A Royal Navy helicopter has crashed onto the deck of a naval ship off the Dorset coast.

Three Navy personnel were injured when the Sea King helicopter hit the Royal Fleet Auxiliary training vessel Argus.

The injured crew members were taking part in a "deck-handling" training operation when the helicopter's rotor blade hit the ship.

An inquiry is now set to be launched into the incident, which happened in Lyme Bay, 15 miles west of Portland Bill at about 1300 GMT on Wednesday.

Critically injured

All three casualties had to be airlifted to the Dorset County Hospital where they were treated for their injuries.

One was later transferred to Southampton General Hospital's cardiology unit where his condition was described as "critical".

A second was being kept overnight in the Dorset County Hospital for observation while the third was released having suffered cuts and bruises.

A spokesman for the Royal Navy, which has not released the men's identities, said: "We do not know what went wrong.

"The exercise was a deck-handling one. They were just practising drills and landing and taking-off procedures.

"For some reason the helicopter crash-landed back on deck.

"Tomorrow morning (Thursday) they will launch an inquiry into what happened."

The helicopter, which escaped serious damage, was a Sea King from 848 Squadron based at the Royal Naval Air Station at Yeovilton in Somerset.

After the accident, it was secured to the Argus, which was due to make its way to an undisclosed port.