Vandals are terrorising gardeners on one of south London's biggest set of allotments - with crimes ranging from cooking owners’ food in sheds to making off with machetes.

About 40 sheds have been broken into in the past six weeks at the Rosendale Allotments, in West Dulwich, with growing concern at an escalation in the seriousness of offences.

What started with sheds being broken in to and alcohol and food stolen, has grown in recent weeks to a number of knives being pinched and a shed being burnt down.

Police carried out a number of surveillance operations at the 450 allotments, in Rosendale Road, because of concerns the knives could be used in gang violence.

Cops feared the blades were stolen ahead of the Notting Hill Carnival by gangs aiming to use them at the event, police sources revealed.

Rosendale Allotments lettings and membership officer, Pek Choo, said: “It is distressing. We have always suffered from people stealing our produce, but what has been going on recently is like nothing we have experienced before.

“These must be people looking for a kick, but it is at the expense of so many people.”

Offences have included using a staple gun to staple sheds, stealing radios, cooking baked beans and other food stuffs in the sheds, trashing the inside of one with food, and stealing alcohol stored inside.

Gardeners believe the vandals have been getting in over one of the fences, after barbed wire was pushed down.

Mrs Choo said the £34-a-year rent paid for each allotment was not sufficient to improve security, and she said plot owners were reluctant for the place to be “turned into Fort Knox”.

Thurlow Park ward councillors confirmed there may be an option to use council funds to better security.

Mrs Choo said the landowner the Dulwich Estate had told them it was unlikely to fund any security improvements.

The police were contacted for comment about the vandalism but did not comment in time for our deadline.