An eight-month-old baby boy lost in the chaos after a truck rammed into a crowd in the French Riviera city of Nice killing at least 84 people was tracked down through Facebook on Friday.

Tiava Banner -- who said she was not the mother of the baby -- sent out an appeal on Facebook looking for any information on the whereabouts of the child who had been lost in his blue stroller when the rampaging truck sent hundreds fleeing in panic as they watched Bastille Day fireworks.

The post was shared thousands of times until it was updated with: "Found! Thank you Facebook and all those who helped us."

A member of the family contacted by AFP on Friday said: "A young woman found him and took him home with her. She then went online and found the photo of the baby on Facebook."

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PHOTOS: Truck strikes crowd in Nice, France during Bastille Day

The woman then contacted the baby's parents.

Dozens of other people appealed through social media to find missing loved ones.

"We are worried to death", "We haven't heard from him since he went to see the fireworks", were some of the messages.

Many of the missing were children and teenagers.

Authorities said Friday that two children were among the dead and around 50 children were in hospital.