A scam video purporting to be a goodbye message from Robin Williams is circulating on Facebook, according to security firm Symantec.

Victims are said to be taken to a fake BBC News website, and are instructed to share the fake film allegedly taken from the deceased comedian’s phone before being allowed to watch it.

Satnam Narang, security response manager at Symantec, said: "Over the years, scammers have used both real and fake celebrity deaths as a way to convince users to click on links and perform actions.

"From Amy Winehouse and Paul Walker to the fake deaths of Miley Cyrus and Will Smith, scammers are opportunistic and always looking for ways to capitalise."

Once the link has been shared victims are not presented with the video, but are instead asked to download a programme or fill in a survey, which has led Symantec to believe the scammers are earning money through an affiliate scheme.

The fraudsters are also said to have manipulate Facebook Open Graph metadata to claim that more than 28 million people have commented on the video, and that more than 24 million have shared it.

"We have alerted Facebook about this scam campaign and they are taking steps to block the offending URLs," Narang added.