Teaching staff prevented an angry parent gaining access to the school and confronting a pupil over an alleged incident outside school grounds.
A spokesman for Rainhill High School confirmed a parent had attempted to gain access to the Warrington Road school.
It is believed the parent intended to confront a pupil about an incident that occurred outside of the school involving their child.
The nature of the incident, which took place on Thursday, June 7, is unclear but is believed to relate to allegations of bullying.
Earlier this year, in an unrelated incident, footage emerged of a Rainhill High pupil threatening to shoot another pupil. Watch the video here: https://www.sthelensreporter.co.uk/news/video-13-year-old-st-helens-girl-told-she-would-be-shot-by-bullies-1-9044275
Police were informed about the incident.
A school spokesman said: "A parent did come into the entrance to the school looking to confront someone else’s child about an incident that had occurred outside of school.
"Thanks to the prompt action of staff, no children were hurt and the parent did not gain access to the building.
"The school have informed the police about this incident."