Detectives are today hunting a man they believe is behind a series of rapes.

Four women, aged between 16 and 25, have been attacked as they walked alone in Hounslow and Richmond.

Police believe the rapes - the first of which happened on Valentine's Day - are linked because of similarities in the description given by the victims and the geographical location of the attacks.

And they are appealing for other victims who may not have reported an attack to come forward.

The first attack happened at about 3am on Valentine's Day in Inwood Road, Hounslow. The woman was pulled to the ground and raped.

On Sunday, February 22, the man struck again, approaching his victim from behind as she walked along Hounslow Road at about 3.30am.

Police said the third attack happened at 11.45pm on Thursday, April 30, as the woman walked into Crane Park from Hospital Bridge Road, Twickenham.

Her attacker ran off into Crane Park.

The most recent attack happened shortly after midnight on Monday, May 4, on a footpath between Telford Road and Harvey Road, Hounslow.

Detective Inspector Andy Perrott, from the Met Police's Homocide and Serious Crime Command, said: "We want to appeal to anyone who may have witnessed the attacks and anyone who may know the suspect.

"There may be more victims. In particular there may be people who were followed by a man but thought nothing more of it. Someone may have approached them in suspicious circumstances and they thought nothing more of it."

In all four cases, police say the attacker was in his mid to late 20s, with chubby cheeks and thick eyebrows and had a dark complexion.

Two of the victims said the man was wearing a sweet-smelling aftershave.

High visibility and plain-clothed police officers will be carrying out patrols in the area and handing out leaflets with safety advice.

Police are reminding women travelling at night to be vigilant and wherever possible to try to walk with a group of friends, to pre-book and use licensed taxis and to keep to well-lit roads.

Anyone with information should call the incident room on 020 8785 8244 or Crimestoppers anonymously on 0800 555 111.