A man in a blue van allegedly tried to snatch a 12-year-old girl as she walked near a school to pick up her younger brother.
The child was followed by a Ford vehicle in Basildon, Essex before the driver got out and tried to grab her, it was claimed.
A primary school has since texted parents to warn them about the incident, which took place at around 4.10pm on Wednesday.
It added that the girl was chased but managed to get away.
The girl's mum, who wishes to remain anonymous, said her daughter has been left terrified to go to school.
She told the Basildon Echo : "She's shaken up and is scared to go to school. She wants to help others and she feels quite lucky but she worries others may not be."
The driver watched from his van before parking up and walking into the girl's path, it was claimed.
He is then alleged to have reached out and attempted to grab her as she tried to get away.
The mum said the street was quiet at the time with no parents or children in the area.
She added: "You see it in films and hear about it but you never think it could happen to your children and she was almost taken.
“It’s absolutely devastating and makes me feel sick to think people like that are in society and it’s so close to home too."
In its message to parents, Whitmore Primary School relayed the incident and warned them to be "vigilant".
A spokesperson for Essex Police said: "We are aware of a social media post relating to an incident that is reported to have occurred in Bower Lane, Basildon, at around 4.10pm on Wednesday 29 June.
"Our enquiries are ongoing, and we are appealing for anyone with information to get in touch."
It comes over a month after a separate incident in Ringwood, Hampshire, where two men attempted to kidnap a two-year-old girl with her mum.
The men showed an interest in their dog, before one of them allegedly picked up the girl and ran with her to a nearby housing estate on the morning of May 11.
The toddler was let go after the dog bit the man on his leg, said Hampshire Police.
In an update on May 22, the force said it was "working really hard" to catch the two men and determine the exact circumstances of the kidnap.
Anyone with information relating to the Essex incident is urged to phone police on 101 quoting 471 of July 3.