The 28-year-old singer was due to play at the Allianz Stadium tonight (15.07.16) as part of her 'Anti World Tour' but has pulled out following the tragedy, which saw a truck plough into a crowd of people who were celebrating Bastille Day last night (14.07.16).
Rihanna was in Nice when the attack took place but her representative has confirmed to Billboard that "she's safe".
Nice mayor Christian Estrosi confirmed on Twitter that the Bajan beauty has cancelled her show and also revealed the city's jazz festival won't go ahead, and that flags will fly at half-mast today.
Interior Ministry spokesman Pierre-Henry Brandet said afterwards that the lorry driver had been "neutralised" and that there were no hostages taken.
The horrific attack comes just months after Eagles of Death Metal were caught up in the terrorist attacks in Paris, France, in November when their concert at Le Bataclan theatre was stormed by gunmen.
As well as the mass shooting at the venue, in which 89 people were brutally killed, three suicide bombers struck near the city's Stade de France football stadium.
Just last month, a security guard killed 49 people in a terrorist attack at gay nightclub Pulse in Orlando, Florida.
Several celebrities paid tributes to the victims, including Taylor Swift.
She took to her Instagram account to share a handwritten note which began "To the families of..." and listed all 49 victims of the mass shooting.
She added the message: "As you bury your loved ones this week, please know that there are millions of us sending you love and our deepest sympathy in the face of this unthinkable and devastating tragedy."
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