A memorial service has been held in Antarctica to honour three Canadians who died in a plane crash there last week.

The three employees of Calgary-based Kenn Borek Air were killed when their Twin Otter slammed into Mount Elizabeth on Wednesday. The victims’ bodies have not been recovered because of poor weather conditions and the dangerous place the plane went down on the mountain.

The U.S. National Science Foundation held the ceremony at its Amundsen-Scott South Pole Station.

The agency says the dead men made the ultimate sacrifice while supporting scientific research in a remote and hostile environment.

American and New Zealand searchers did recover the voice recorder from the plane's tail and it's being sent to Ottawa to be examined. Canada’s Transportation Safety Board is investigating the crash.

Searchers said they may try to recover the mens’ bodies in October, when winter in Antarctica is over.