Refugee Martha Danga, 41, and her partner Shame Murimi, 40, fled Zimbabwe in 2001, and have spent seven years buying and collecting electrical equipment, clothes, shoes, school books and toys to make lives better for families in the African capital, Harare.

Now their dream of returning to Africa, when the country is safe enough to do so, with the container-load of goods for their family and the city's poor has been destroyed.

The goods, valued at £50,000, were destroyed when the lorry they were being stored in was deliberately set on fire on private land near their home in Bradford early on Monday.

Mum-of-three Martha, a support worker at a care home, said: 'We are destroyed. We are devastated and our family is devastated. We have been working for seven years for nothing.

"We do not know why people would do this. We were looking forward to going home after the political situation changed but now we do not know what will happen."

The couple were woken shortly after 1am by firefighters who had been called to the small, privately-owned car park where three large trucks belonging to them were parked.

Two were empty and left untouched but the third, fully-laden with goods, including items donated by well-wishers for Zimbabwean children, was ablaze.

A Fairweather Green fire station spokesman said the Iveco lorry was a write-off along with most of the goods inside. "There were also other arson attacks on cars in this area a couple of weeks ago," a fire investigation officer said. "We are looking at the incident being arson."

Police confirmed they were investigating the incident and called for anyone with information to contact them on 08456060606 or anonymously via Crimestoppers on 0800 555111.