A nationally important collection of lilacs has been raided by thieves.

Withdean Park, in Brighton, is famed for its collection of lilacs, the second largest in the world with more than 250 types, and has been designated by the National Council for the Conservation of Plants and Gardens as the national reference collection for the species.

But moves to restore the collection to full status, which it held until 2007, has taken a blow after the bushes were targeted on Thursday.

Phillipa Shaw, the co-ordinator of Friends of Withdean Park, said: “Someone or some people took a saw to most of the new young lilacs and some of the 40-year-old ones.

“We found a lot of lilac-coloured string under the bushes. They have obviously been stolen and tied up for the purpose of selling them to the public.

“If you see them, you should remember where they have been stolen from.

“Our bushes have been left devastated. I wonder what these people would feel if we did it to something they loved? With all the hard work the Friends of Withdean Park have put in to save this collection, this has left us reeling.”

Ms Shaw said groups of people had been spotted in the area with pruners in the morning.

Geoffrey Theobald, Brighton and Hove City Council’s cabinet member for environment, said: “We are very concerned about this incident. It is not someone picking a bunch of flowers, it is theft and we will be notifying the police.

“Several hundred lilac bushes have been cut and the flowers have been removed, we can only assume to be sold.

“It is very disheartening for the Friends of Withdean Park, who take great pride in the area, and all those other park users who enjoy this open space.”

The Friends of Withdean Park will be holding its fourth Lilac Lark on Sunday May 10 from 2pm until 5pm to help raise funds for the maintenance of the park.

Anyone with information about the theft should call Sussex Police on 0845 6070999.