Police were called to a Burnley primary school this week after a van was spotted acting suspiciously outside.
A white van pulled up at St Augustine’s RC Primary School, in Lowerhouse Lane, and the driver shouted to pupils who alerted staff.
The headteacher sent a text message to parents following the incident at 11-20am on Tuesday, urging them to be vigilant and report any suspicious behaviour.
Children who were playing outside told teachers the driver of the vehicle shouted to them.
Frightened pupils then ran inside and alerted staff who got all the children inside the school building and called police.
Parents have taken to Twitter and Facebook to voice their concerns.
A police spokesman said officers were trying to trace the owner of the van and stressed no attempts had been made to abduct a child. He also urged people to ignore rumours circulating on social networking sites.
“We would urge people to report any suspicious behaviour to the police, he said.
The school refused to comment but a spokesman from Lancashire County Council said: “The school sent a text message out to parents to remind them to be extremely vigilant.
“The school has taken the appropriate action.
“The school itself is quite secure and it is difficult for people to get onto the premises.
“These things are very rare and people do have legitimate reasons for stopping outside schools.”