The search is to resume for a plane which vanished in Brazil with four British businessmen on board.
Teams from the Brazilian air force, police and volunteers will scour an area of jungle and sea in the north-east of the country.
As the operation entered its fourth day, sources said efforts were being made to obtain extra resources in a bid to find the aircraft.
The search was launched on Friday night when the twin-engine Cessna 310 aircraft lost contact with air-traffic controllers minutes before it was due to land in the coastal city of Ilheus.
Nigel Hodges, 52; Alan Kempson, 46; Sean Woodhall, 43; and Ricky Every, 41, were travelling from Salvador to Ilheus as part of a trip to check out a proposed housing development planned by Worldwide Destinations.
The international marketing and development company, which has its headquarters in Malaga, Spain and a UK office in St Neots, Cambridgeshire, says it specialises in creating luxury property developments in new emerging markets.
Entrepreneur Mr Woodhall, a Swiss resident, is its president, according to Michael Lynn, a long-time friend and colleague.
Mr Lynn said: "Everybody is hoping that there will be a positive outcome. We have to stay positive, but it has been a long time now.
Mr Every lives in Brazil and works for Worldwide Destinations there, Mr Lynn said.
He added that Mr Kempson and Mr Hodges - who are directors of a British sub-prime mortgage business which currently has financial difficulties - were potentially going to do some work with Worldwide Destinations.
