A convicted child rapist is free to loiter where youngsters play after a police effort to ban him failed.

The Streatham man, who cannot be named for legal reasons, was convicted in 1997 of a number of charges involving children, including rape, buggery and indecent assault.

The 71-year-old was released after having his 12-year jail term reduced to eight years following a High Court appeal.

Lambeth police believe he is still a threat to youngsters, having been allegedly spotted at least twice hanging around near children on Streatham Common.

But at Camberwell Green Magistrates' Court on Monday, a district judge turned down a police request for him to be given a Sexual Offences Prevention Order to control his behaviour and prohibit his access to children.

Such civil orders have been used to prevent convicted paedophiles from loitering around schools or playgrounds.

On July 1 last year, the man was allegedly seen in close proximity to children on the common. He was recognised by a psychologist working at Wandsworth prison, who rang the police.

It is claimed he was then seen in the same place six weeks later by Lambeth police's Jigsaw unit - the officers responsible with tracking hundreds of offenders in the borough who remain a threat on release.

But District Judge Timothy Pattinson said he did not believe the evidence presented by police proved it was necessary to make the order to protect children from "serious sexual harm" at the hands of the man.

Neither the police nor the court would reveal details of the desired order.

The Streatham Guardian became aware of the case based on brief information published by the court.

Police would not reveal if the man had been seen further times near children in the park or in other locations in the borough, or if they would again seek to place an order on him.

A police spokeswoman said they did not comment on decisions of the court.

If the application for the order had been successful, the man - who is on the sexual offenders' register indefinitely - faced jail if he breached its terms.

Some 300 registered sex offenders of different degrees of risk are currently being observed in Lambeth by the borough's Jigsaw unit and the probation service.