Are you certain they are rabbits and not hares?
The Hunting Act makes it an offence to hunt a wild mammal with dogs, apart from the tightly-drawn exemptions set out in the Schedule to the Act. The ban covers the hunting with dogs of all wild mammals, including fox, deer, hare and mink. The Act also completely bans hare coursing.
The exemptions from the offence of illegal hunting permit the following types of hunting:
� Stalking and flushing out
� Use of a dog below ground, in the course of stalking and flushing out, to protect birds being kept or preserved for shooting
� Hunting rats and rabbits
� Retrieval of hares which have been shot
� Falconry
� Recapture of wild mammals
� Rescue of wild mammals
� Research and observation
These exemptions are subject to strict conditions (eg on the number of dogs which can be used in stalking and flushing out (two) and on obtaining permission to carry out the activity on the land on which it is to take place). The Schedule also requires that anyone intending to rely on the stalking and flushing out exemption must ensure that animals flushed out are shot as soon as possible afterwards by a competent person.
http://www.defra.gov.uk/rural/hunting/hunting_ qa_a.htm