A Woodside Park school faces a race against time to open for the new term after a massive fire destroyed almost half of the building.

Seven classrooms were completely gutted in the blaze at Frith Manor Community Primary School in Lullington Garth shortly after 5.30pm on Thursday.

Speaking at the scene on Thursday the school's new head teacher Reginald Herring, whose first day is on September 3, said: "I am absolutely stunned I don't know where to start. I had a call from the school secretary over an hour ago and I'm just absolutely shocked.

"This is the main year one to three classroom block and there is a computer room in there and the main toilet room. Six classrooms are totally lost. The new term is due to start for the children on September 3. At the moment, until we have met with the local authority and governors we are not going to make any decisions."

Firefighters using six fire engines battled with the blaze for more than five hours at the 1930's school. Smoke billowing from the roof could be seen as far away as Golders Green. Police cordoned off Lullington Garth at its junction with Frith Lane causing traffic jams in nearby roads.

Assistant divisional officer Rob Simpson, of Southall fire station, said almost the entire roof of the block was alight when firefighters arrived.

"There is about 50 per cent damage to the whole school. There have always been difficulties with schools and fires for a variety of reasons. There is the obvious reason of children and vandalism. But they are unoccupied buildings for long parts of the year and if a fire starts it's a certain magnitude before people get to know about it. We couldn't send people in there readily because it was a dangerous structure."

Dawn Stevens, of Wentworth Park, Finchley, saw the blaze from her home. "I noticed the smoke rising up over the garden. From my loft window I had a view that was quite horrifying. I could just see the flames racing through."

Ezri Erlanger, of Temple Fortune Road, said: "I saw the smoke in the sky from Golders Green and came over to see what was going on."