The authorities in France have urged social media users to act responsibly following false rumours about the attack in Nice on Thursday night.
The Twitter account of the French government posted a message, appealing to people to share only reliable information from official sources.
It comes after false information and pictures were circulated on the internet as the situation in Nice was unfolding.
Fake: Eiffel Tower attack
Pictures and tweets of a fire around the Eiffel tower also began circulating, suggesting a co-ordinated double attack, but again the information was false.
It did not stop social media users sharing the rumour and prompted a correction from police in Paris.
Fake: False suspects named
The suspect in the attack has been named locally as Mohamed Lahouaiej-Bouhlel but a number of images of other people, falsely accused of involvement, have been published online, including by major news organisations.
Veerender Jubbal, who is Sikh, was incorrectly named as a terror suspect for a second time, and a doctored image of him posted online.
Not only was he wrongly identified as being responsible for the attack in Nice - the doctored image of Mr Jubbal was also circulated after the Paris attacks showing him wearing an explosives belt and carrying a Koran. @SikhProf tweeted: "People are wrongly identifying my Sikh friend as being responsible for the #Nice attack. Please help end the rumours."
Fake: Allahu akbar was heard
Messages were circulated that the truck driver shouted Allahu akbar, which is Arabic for God is great.
As yet, no official source has said this happened.
French prosecutors say no group has admitted carrying out the attack but it bears the hallmarks of jihadist terrorism.
Fake: Calls to find lost relatives
Following tragic events many appeals for help tracing loved ones are shared on social media. Facebook page SOS Nice has been set up to find missing relatives, probably because within hours of the Nice attack false pictures of victims were being shared on social media by trolls.
This man's picture appeared online as a purported victim in Nice, but it has been shared before on social media as a supposed missing person following theEgyptAir crash in May, the attacks at Ataturk airport in Turkey last month and the Dallas shootings.
Many social media users have been quick to point out the fakes and help dismiss the misinformation. @Lil_RoxaNe tweeted that the picture of the man above was a fake, and others said people who posted such fakes should be ashamed.
The Nice attack provides another example that some people take advantage of tragedy to spread false rumours online. It is an increasing problem for those affected by such events and those searching for the truth.