Investigations are continuing at the site of a helicopter crash in the Mourne Mountains in which three people were killed on Saturday.
Charles Stisted, Ian Wooldridge and their pilot, who has not yet been named, died when the aircraft crashed.
The men were travelling back to England from County Tyrone, where they were part of a private shooting party at a country estate.
Air accident investigators have been gathering and cataloguing evidence.
A police spokesman said significant resources were dedicated to the recovery.
The helicopter is believed to have taken off from Enniskillen, County Fermanagh, and crashed at about 1600 BST in an area known locally as Leitrim Lodge, between Hilltown and Rostrevor.
Mr Stisted, 47, was chief executive of the Guards Polo Club at Windsor and a personal friend of the Prince of Wales.
Clarence House said Prince Charles, the Duchess of Cornwall, and the princes William and Harry were "shocked and deeply saddened" by news of the crash.
Mr Wooldridge, from Windlesham, Surrey, was also a member of the Guards Polo Club.
Together with his brother Graham, he ran a £40m-a-year demolition and construction company.
Mr Wooldridge was a prominent figure in Dublin-based Harcourt Developments, the property company involved in the development of the Titanic Quarter in Belfast.
A Harcourt spokesperson said: "Charlie was an enigmatic and well-respected individual who we got to know through our sponsorship of the Queen's Cup."
"Ian's experience and judgement were valued by all in Harcourt/ Titanic Quarter and his contribution will be sorely missed."
Guards Polo Club chairman Colonel Paul Belcher said Mr Stisted had been "highly regarded" and "much loved".
Colonel Belcher said Mr Wooldridge was a "popular player and generous supporter of the club".