At least three dead whales have been found in the central province of Nghe An over the last month, local media reported.
In the latest incident, on Monday afternoon, some tourists found the carcass of a whale on Cua Lo Beach.
The whale measured around one meter in length and 40 kilograms in weight. There were some wounds on its body.
Local fishers then held a ritual burial for the whale, which they considered sacred.
Three days earlier, a 44-year-old fisher also found a dead whale near the same beach. The whale was around 1.5 meter-long and weighed 80 kilograms.
On March 16, another fisher in Nghi Loc District nearby found the carcass of a whale ashore. The body had started decaying. The whale was around 1.5 meter-long and weighed around 50 kilograms.
While some local fishers believe that beached whales are signs of good luck, environmentalists are very concerned. They say it is unusual to see several dead whales in a particular place within a short period of time.
There have been several media reports and studies linking recent whale deaths around the world to the intense El Nino weather conditions and also to climate change.