A dog warden at Wandsworth Council says he has seen a rise in the number of potentially dangerous dogs on the streets.

Figures released today, obtained by the Liberal Democrats, reveal London has seen the sharpest rise in the number of people being treated for dog bites in hospitals.

In the capital, there was a 119 per cent increase in A&E admissions for dog attacks on under-18s in the past four years.

Warden Mark Callis told Radio 1's Newsbeat: "We are seeing an increase in these breeds, but also an increase in a particular type of owner."

But you can "never blame the dog for its behaviour", he added.

The NHS statistics show the number of dog attack victims in England attending A&E has risen by 43 per cent in the last four years to nearly 3,800 a year.

Hospitalisation of children and young people has risen by a fifth, with 58 per cent more adults being admitted to A&E as a result of dog attacks over the same four-year period.

The hospital admission statistics revealed a strong regional variation.

The Greater London Authority, Metropolitan Police, RSPCA and Battersea Dogs and Cats Home are launching a campaign on responsible dog ownership.

Wandsworth is among the local councils using bylaws and ASBOs to deal with owners who fail to control their dogs.

Liberal Democrat health spokesman Norman Lamb called for a review of the Dangerous Dogs Act, saying more needed to be done to make people aware of the risks of irresponsible dog ownership.

Mr Lamb said: "There is a worrying trend in some areas of using dangerous dogs as fashion accessories or, worse still, as weapons."