A HEADTEACHER is furious a fire alarm didn’t warn his pupils to evacuate despite being upgraded a month ago.

A science technician at Harwich and Dovercourt High School smashed the alarm glass when he saw smoke coming from the roof last week, but warning bells did not sound.

Hundreds of children abandoned the school in six minutes after emergency exits were automatically released.

Two engines from Dovercourt attended the school in Hall Lane at 11.18am on Wednesday, January 9, but the fire was out as they arrived. They left the scene at 11.43am.

The school has its fire alarm system upgraded in December which was checked by Essex Fire Service.

Headteacher Nigel Mountford is investigating how it happened.