A tourist who was CEO of the American arm of the British publisher that launched Harry Potter in the UK was killed off Italy's Amalfi Coast after the "gommone" or motorboat she was riding on with her family collided with a sailing vessel rented for special events, according to the Prosecutor's office in Salerno, which is conducting the investigation into her death.

Adrienne Vaughan, 45, was the president of Bloomsbury US, the British parent company confirmed to CNN, and she was traveling in Italy with her husband and two children, who survived the accident.

The sailboat company confirmed by telephone to CNN its 45-meter boat, the Tortuga, had 80 guests on board, including Americans and Germans, when the tragedy occurred.

The office of the public prosecutor of Salerno, Marinella Guglielmotti, confirmed to CNN by phone an investigation into the skipper of the boat Vaughan and her family were on has been opened after initial toxicology reports showed he had more than the legal limit of alcohol in his system. Further tests for drugs will be released Friday afternoon in Italy.

The captain of the Tortuga did not test positive for any substances and is not under investigation, the prosecutor's office said. Both boats were approaching the Fiordo di Furore area of the Amalfi Coast around 6 p.m. local time on Friday when the accident occurred.

Vaughan was thrown into the water and died after being injured by the Tortuga's propellers, the Salerno prosecutor's office confirmed. The Amalfi Coast Guard unit responded to the accident. She was treated at the scene, and taken to Amalfi port and then to the emergency room in Castiglione, but died before she could be airlifted to Salerno because a helicopter ambulance arrived at 7 p.m. local time, according to the prosecutor's office.

Both boats have been sequestered by the Salerno Port Authority pending the investigation.

The U.S. embassy in Rome did not have information about the case or any support they are giving when reached by CNN.