A teenage boy has been arrested over alleged threats made on social media about a school in York.
Police attended the Joseph Rowntree School on Haxby Road at about 09:30 GMT in response to an alert from a parent about suspected threats to the school.
A 14-year-old boy was arrested and taken into custody, North Yorkshire Police said.
The school said all of its students were safe and any potential threats were being looked into fully.
"To reassure parents following a number of rumours on social media, there was no-one with a gun or any other weapon and no-one has been injured," the police force said.
"We realise the sight of police officers at the school caused concern.
"However we hope parents are reassured that we take all such allegations seriously and worked with the school to minimise disruption and ensure the safety of all pupils," it continued.
Maxine Squire, the school's assistant director for education and skills, said: "We would like to reassure parents and pupils that the threats made on social media about Joseph Rowntree School have been looked into thoroughly.
"The safety of pupils and staff is a priority and we are working with the school and police to provide ongoing support."