The driver of a speedboat which killed two members of the same family as it raged out of control was not attached to a safety device designed to cut power in an emergency, investigators have said.
Nick Milligan, 51, the managing director of Sky's advertising sales division, Sky Media, was declared dead at the scene in Padstow, Cornwall, with his daughter, Emily, eight, following the incident on Sunday, May 5.
"The [boat] was fitted with a kill cord, but this was not attached to the driver at the time of the accident.
Consequently, when the driver was ejected from the boat, the kill cord did not operate to stop the engine and the [boat] continued to circle out of control, and at speed."
It said the boat ran over members of the family "a number of times" as it circled in the water.
More top news
Scotland Yard said the male youths will appear in custody at Westminster Magistrates' Court on Saturday.
The family of Oliver Dearlove urged people to "think again" before using their fists, as the man who killed him began a six-year jail term.
London Fire Brigade took Southwark Council to court on four charges in relation to safety breaches at Lakanal House in Camberwell.