The school was closed following the scare on Tuesday

Crookhill Primary will remain closed until at least Monday, while three boilers under a classroom are examined.

Two teachers and 25 children, aged nine and 10, were taken to hospital on Tuesday after complaining of dizziness and sickness.

Eight were found to have raised levels of carbon monoxide and were treated with oxygen.

Investigators from the Health and Safety Executive (HSE) and specialist engineers are examining the suspect boilers.

'Isolated incident'

Gateshead's Director of Public Health, Dr Mark Lambert, said people living in the area should not be alarmed.

He said: "We agree with the precautionary measures taken by Gateshead Council in evacuating the school but this appears to be an isolated incident and we do not anticipate any more children or staff developing symptoms."

The children were treated at South Tyneside District Hospital, Newcastle General and the Queen Elizabeth in Gateshead.

Bob Jarman, A & E consultant at Gateshead Health NHS Foundation Trust, said the levels of carbon monoxide measured were "not thought to be worrying."

Pam Waldron, head of HSE operations in the North East said: "The focus of our enquiries is the three gas fired boilers underneath the classroom and their fluing arrangements.

"We issued a notice that the boilers should not be used and access to the boiler room is currently under HSE control."