The manager of a Pinner stable yard who lost 100 tonnes of hay and straw in a huge blaze last night says he is “devastated”.

Tim Wood, manager of Joel Street Stables, was left assessing the damage this afternoon from the fire last night which destroyed a large barn he rents to store winter feed for horses.

Firefighters are still dampening down the smouldering structure, which caught alight at just after 10.45pm last night, and police are at the scene investigating the blaze, which is being treated as arson.

Mr Wood told the Harrow Times : “I’m devastated – I don’t know what to think to be honest.

“We’ve rented this place for 12 years and it’s the second time it’s happened.

“It was the entire winter feed for the horses. I don’t even want to think about how much it’s going to cost me.”

Firefighters rescued one horse, a 14.1 hand-high piebald named Diamond, from the raging fire at the barn, and protected others in the field opposite, while two people who escaped were treated for smoke inhalation.

It took fire crews more than three hours to control the blaze, and they remained at the scene throughout the night to make sure it did not reignite. Tractors are now dragging away bales into surrounding fields.

One neighbour, who lives opposite the barn but asked not to be named, said that everybody in the street was out in the early hours watching the blaze, which had scared her two children.

Owner of the rescued horse, Bernadette O’Neill, appealed for help for someone to house Diamond, who was being kept in isolation in the barn because he is suffering from the contagious disease strangles.

She said: “It’s awful, I don’t know why anyone would do this – she could have been burnt alive.

“She has to be more than 33ft away from the other horses and I don’t know what I’ll do unless someone can help me.”

Anyone who can help should contact her on bernadette-oneill@hotmail.co.uk