Lorry driver Tony Hewitt has condemned vandals who destroyed his cargo of yeast causing £18,000 of damage and forcing him to quit his job.

The 61-year-old driver who works for Belgian food-transport company Sitra says the attack was malicious.

Mr Hewitt, from Ingram Street, Malmesbury, had parked his articulated lorry in a layby in Filands Road on Saturday July 24.

But between 6pm and 11pm, the fridge trailer's temperature gauge was increased from 0c to 25c, ruining its ten tonnes of yeast.

Vandals next poured sugar into the fuel tank of the lorry's refrigerator.

The destruction of the yeast alone amounted to £10,000 and the vehicle repairs plus the loss of business cost around £ 8,000.

Because of the security fears, the company has stopped Mr Hewitt from returning home at weekends.

He has been stationed in Calais or Dover since the incident.

But lonely for his wife Sylvia, Mr Hewitt is planning to quit his job delivering yeast to Belgium.

He hopes to drive a non-refrigerated lorry for the company to France instead because this means he could park it safely in Malmesbury at weekends.

Mr Hewitt said: "When you drive a fridge trailer, you have got to be careful. Whoever has done this definitely knew what they were doing. When you are increasing the temperature gauge you have to lock in the settings or it will revert automatically back. This was malicious. I would never have thought of it and I drive the lorry.

It was very uncomfortable. It has stopped me from coming home at the weekend. Normally I would park the lorry in Station Yard, but the refrigerator inside creates a lot of noise, so I parked it at Filands not to disturb anybody. I would like to know why anybody would go around with a bag of sugar on a Saturday night."

He added: "When we came to Malmesbury we were told it has got one of the lowest crime rates in the country. But this is something that will sit with me for a long time."

Anyone who saw anything suspicious can call police on (01666) 822222.