Wigan schools are urging parents to pick their children up after a man in a white van "tried to snatch" a young boy.
St Catharine's C of E School in Scholes has issued a warning for schools across the borough following the "serious incident" on Thursday evening.
Nicola Goulding, head teacher of the primary school, said: "A little boy was walking home near the funeral directors when a man in a white van, in slowly moving traffic, shouted to him to come over.
"When he hasn't, they have opened the door and tried to grab him. They have not touched him, they didn't manage to make any contact.
"He ran home to his mum and the police were called.
"There seem to be more and more reports of different things like this at the moment. It's worrying.
"We have asked parents to be vigilant and pick their children up but at the same time we don't want to scare people."
The school has issued a letter with details about the incident.
Pupils also attended "stranger danger" assemblies this morning and are being spoken to throughout the day in their individual classes.