DETECTIVES are investigating two incidents in the Ruislip-Northwood which they think are linked.

At around 2.45pm on Saturday, police received a report of a sexual assault in The Gravel Pits, Northwood.

A woman in her 20s reported being approached by a man who grabbed her and dragged her into a secluded area of the park.

He then carried out a sexual assault, saying he had a knife to stop her from shouting out.

A member of the public approached and the victim managed to call for help.

The suspect ran off in the direction of Copse Wood Way and the incident was reported to police.

A second incident was reported at around 8.15am on Sunday.

The victim, in her 50s, told officers she had just been attacked in Duck Pond Park, Ruislip.

She said that, while walking through the park, a man put his hand over her mouth and said he would stab her if she started to shout.

He managed to pull her to the floor and attempted to drag her off the footpath into a ditch.

The woman screamed and the maan ran off in the direction of Pinn Way.

The suspect is described as a light-skinned black or Asian man, aged 20-30, around 5ft 8in tall, of slim build, with a bald or closely-shaven head. He was wearing a dark coloured tracksuit.

Anyone with information should call 101 or tweet @MetCC and quote CAD 4511/12Sep. Alternatively, contact Crimestoppers anonymously on 0800 555 111.