The head teacher of a school attended by two teenagers arrested on suspicion of planning terror attacks has told parents pupils' safety is "paramount".
The 14-year-olds were arrested at their homes in Northallerton on Saturday.
In a letter to parents, Northallerton School and Sixth Form College head Chris Byrne said they were working with police to prioritise student safety.
Last month, Mr Byrne wrote to parents to dispel rumours a student had brought a weapon into school.
The latest letter, sent to parents on Monday, said: "Police continue to investigate with an open mind to establish what, if any, offences have been committed.
"We fully recognise that parents and carers have concerns as a result of these arrests.
"We would like to reassure you that the safety of the school is paramount and we are working with the police to support our students and prioritise their safety at all times."
It is the second time in just over a month that the school has written to parents about safeguarding issues.
A letter was sent on 28 September reassuring parents that rumours about a student bringing a weapon into school were untrue.
In that case, Mr Byrne said all necessary precautions had been taken and the school was satisfied there was "no issue to be concerned about".
Since the arrests on Saturday, a number of properties have been searched in the Romanby area and items seized are being examined by police.
The North East Counter Terrorism Unit said the teenagers had been taken to a police station in West Yorkshire for questioning.
They have until Wednesday to question them.
Police have said they believe it was an isolated incident and the wider community was not at risk.