Dart Harbour bosses have issued a safety warning after the tragedy in which a father and his daughter died over the bank holiday weekend after being run down by their own speedboat.

Harbourmaster Rob Giles said: 'I would encourage skippers to be incredibly mindful of themselves, their vessels, their passengers, their crew and other vessels when taking any decision about safety.'

He stressed that the investigation into the accident on the Camel estuary at Padstow had still to be concluded as he added: 'It is an absolute tragedy and our thoughts and sympathies go out to the family.

He added: 'We keep a weather eye on the safety of all craft on the river here and we would encourage people to take all the safety measures possible.'

The investigation in the Padstow accident is likely to concentrate on the use of the kill cord which should cut the engine of any powerful speedboat if the person at the helm somehow loses control.

Mr Giles said: 'With a powerful craft there has to be some kind of fallback if the driver for some reason becomes incapacitated and leaves the controls of the boat.

'Boats of that nature are provided with a failsafe facility, such as a kill cord, but they won't work if they are not used.'

Media company executive Nick Milligan, his wife Victoria and their four children, from Wandsworth, London, were somehow thrown out of the powerful speedboat they were riding in on the Camel estuary at Padstow on Sunday afternoon. The speedboat continued to travel in circles and is believed to have run down the family while they were in the water.

Mr Milligan, 51, and his eight-year-old daughter Emily were killed in the accident. His 39-year-old wife, four-year-old son Kit and daughters Amber, 12, and Olivia, 10, were airlifted to Derriford Hospital in Plymouth.

Mrs Milligan is believed to have lost part of a leg following the accident but surgeons are believed to have been able to save Kit's leg despite his serious injuries.

The two surviving daughters suffered minor injuries and are believed to be recovering well.

Mr Giles said the harbour board used an appropriate level of enforcement regarding the use of all safety equipment.'

He said that the Marine Accident Investigation Branch would be leading the investigation into the accident and predicted it could lead to significant issues regarding 'safety in the leisure boating world'.

'We need to see what the MAIB concludes and I will be watching that with interest,' he added.