Jane Deasy (27) from Dublin, Aisling Butler (26) from Roscrea, County Tipperary, and Eithne Walls (29) from Belfast, Northern Ireland, were returning from holiday on the Rio de Janeiro to Paris flight.

The three had met while studying medicine at Dublin's Trinity College and had qualified in 2007.

Butler's father told the Irish Examiner newspaper that when he heard about the missing plane he initially thought his daughter's flight was due in the following day but decided to check travel details in his deleted emails.

"When I opened it up, a nightmare opened up as well," he said.

"We know Aisling is gone, we are sure of that. It is just about trying to live now. I have to live for my wife and my only other daughter, Lorna."

Julian Erskine, executive producer of Riverdance, the Irish step dancing theatre show, described Walls as "bright and sparkling" and someone who made an impact on everyone she met.

"Anybody who knew her would remember her very fondly. When she wasn't dancing, she was studying. She was always on the go. She was on a mission to be a doctor. It was what she really wanted," he told RTE state radio.

She joined the Riverdance troupe in 1998 when she was 18.

"She would have travelled around the world and then she settled for a year on Broadway when we presented Riverdance in New York. Then she was back with us in the Gaiety Theatre (in Dublin) in 2004," Erskine said.

Meanwhile details emerged of some of the five British victims of the Air France catastrophe, in which 228 people are presumed dead.

One was Alexander Bjoroy, an 11-year-old pupil at Clifton College preparatory school in Bristol, southwest England. A receptionist at the school said: "We are doing all we can to support the family."

Oil worker Graham Gardner (55) from Gourock in Scotland was named by his employers, while the wife of a British engineer, Arthur Coakley, paid tribute to her "fabulous husband".

Patricia Coakley told how her son Patrick phoned her up and asked her "What flight is Daddy on?"

"I dashed home and checked Art's itinerary on the Internet and realised... At first I didn't think it was his flight, then I realised it was his flight," she said.

"I phoned up the company in Aberdeen and they didn't know anything about the plane crash."

Meanwhile, 19 of the French passengers on the plane were returning from a Brazilian holiday won by a company's sales team, the firm told AFP on Monday.

"There was a competition for the best sales reps for the southwest region and nine of them won and went to Brazil for four days," said Laurent Bouveresse, chief executive of the CGED electrical equipment supplier.

The nine, aged between 25 and 35, were allowed to take a friend or partner on the trip as part of their prize, and an executive from regional headquarters in the town of Limoges also went on the trip, he said.

The sales people worked in towns across the region, he added.

"I heard (of the crash) late Monday morning, it was more than a shock, I just can't describe it," he said.