The Halifax Mk. III was shot down by a German Messerschmitt fighter in the early hours of May 25, 1944, killing all seven crew members - volunteers from Canada, England and Zimbabwe.

"Their gravestones have been waiting for 60 years," said Roy Peterson, 68, the younger brother of the plane's navigator, Sidney Peterson.

Roy Peterson, who was seven years old when his brother died, travelled from Canada with his two sons to attend the start of the salvage operation. In an article published in 2002, he had written about how adventurous his older brother was as a child growing up in Winnipeg.

"It's a bittersweet moment," Roy Peterson said. "I'm holding it together right now, but I don't guarantee I'll be able to keep it together when I get back to the hotel."

Salvage project spokesman Marcel Kummel said private donors and the municipal government in the city of Werkendam near where the crash occurred contributed the equivalent of about $390,000 Cdn for the operation out of a feeling of gratitude to those who died.

"This kind of salvage is quite costly nowadays, with dig teams, explosives experts, forensics experts, and you have to clean up hazardous materials" left from the crash, including asbestos, Kummel said.

The Dutch countryside and coast is still dotted with wrecks and live mines left over from the war, and salvage operations are carried out when there is opportunity and funding.

The bomber was one of more than 400 planes that participated in the bombing of Aachen, Germany, intended to disrupt Nazi supply lines ahead of the D-Day landing in Normandy.

The plane, known by its serial number LV905, was returning to base when it was shot down in a crash witnessed by several farmers, including a teenager who is still living.

Until now, only the remains of the gunner, Sgt. George Butler, had been identified and were buried along with an unidentified crew member in the cemetery of Jonkerbos in Nijmegen.

The other five crew members have grave markers in Jonkerbos, but their remains are believed to lie in or around the wreckage of the craft, in a rural area outside the village of Hank in the southern Dutch province of Brabant.

"We laid flowers (on the gravemarkers in Jonkerbos) but nobody was there," Peterson said. "I hope they find something, and we can eventually lay flowers and they will be there."

The salvage operation will take at least four weeks, Kummel said.