Police have increased patrols and knocked doors to reassure families following a spate of robberies in and around an Oxford park.

Gillians Park and the surrounding streets have seen nine people robbed - two at knifepoint - in just over a month.

Police have stepped up their presence in Greater Leys and sent out their dog section and a helicopter to try to find the culprits.

Blackbird Leys Police Community Support Officers (PCSOs) handed out 200 leaflets to park users and neighbours to inform them about the increased patrols.

Det Con Claire Routledge, of Oxford CID, said: "We are continuing to investigate the robberies that have taken place in Gillians Park and I would like to reassure the community the police are doing everything in their power to catch those responsible.

"We have significantly stepped up our patrols around the park, especially in the evening, when the robberies have taken place."

Many of the victims have been foreign students and Det Con Routledge has advised them to avoid being in the park on their own.

Some of the students were punched, and lost lost mobile phones, cameras, iPods and in one case £300. The robberies are not being linked.

People living in the area said the park had also been blighted by drug-dealing and teenagers riding motorcross bikes close to two children's play areas.

A police spokesman would not confirm how many patrols they were making "for operational reasons", but neighbours were positive about seeing more bobbies on the beat.

Sue Bull, a mother-of-one from Marjoram Close, which backs on to the park, said: "I have had lots of trouble with kids playing at the back of my fence.

"Earlier this year they went along and bashed the fence in.

"I wouldn't walk through the park on my own, especially at night. I think the extra patrols are good because they can monitor the area.

"It is great. They need more police on the estate."

PCSO Andrea Ferdinands said: "We delivered around 200 flyers to residents explaining what the police are doing to identify and catch the offenders and also provide crime reduction advice to prevent people from becoming a victim."

The leaflets given out in Greater Leys contained advice to help stop people becoming a robbery victim.