Thursday is the last day for love for thousands of pitbull terriers in France.

Owners of the dog, and other breeds considered a danger to the public, must from now on get them neutered - or face punishment.

Under a new law, owners of un-neutered pitbulls and the related South African mastiff face a maximum penalty of six months in prison and a 100,000 franc fine (about £9,600).

Staffordshire terriers, American Staffordshire terriers and Japanese Tosas without a certificate of pedigree must also be neutered.

The law is aimed at eradicating dogs considered a risk to the public within 10 years. The government hopes that the dogs - which may not be imported - will die out if they cannot breed.

Half may miss deadline

But according to officials, fewer of the 20,000-40,000 pitbulls estimated to be in the country will have been neutered within the deadline.

"Our vets have been unable to discern any increase in the number of sterilisations. The behaviour of dog-owners remains unchanged," said Veronique Blanchetti, vice-president of the Association of Veterinary Surgeons.

The government action followed a number of attacks on people by pitbulls, mainly in poorer suburban areas.

Police, who say the dogs are commonly used by drug-dealers and other petty criminals, welcomed the move.

"Up to now we had no way of cracking down," said Marc Forest of Paris police's dog unit. "(The law) is what we've been needing."