Criminal gangs behind a lead and copper scrap metal crimewave could be responsible for a rise in bike thefts.

There has already been 55 more bikes stolen in the first two months of this year across Oxfordshire compared to the same period last year.

And in many instances the bikes were not brand new models.

Police are now investigating whether this sharp rise is linked to the same organised criminal gangs behind the theft of lead and copper from buildings across the county.

Already this year there have been 338 bikes stolen compared to 283 in the first two months of 2007.

Throughout the county dozens of pubs, churches and homes have had their roofs stripped of lead and copper.

The metal is sold on at scrapyards for a healthy profit in a what has become a national multi-million pound crimewave.

Roger Foster, crime reduction advisor for the Vale of White Horse, said police are investigating a number of reasons for the recent spate of bike thefts.

He said: "We have a lot of metal thefts and we are wondering if there is a link with older bikes being stolen for their scrap value.

"It is something we are definitely considering."

In Oxford bike theft has increased from 187 to 239, in the Vale of White Horse reports have risen from 20 to 37 and in South Oxfordshire there has been 26 this year compared to 24 in 2007.

However, bike theft in West Oxfordshire and Cherwell has fallen from 23 to 20 and 27 to 18 respectively.

Mr Foster added: "We do have crime trends and often it's difficult to put your finger on it.

"The value of bikes these days is going through the roof.

"But we are seeing lots of old bikes as well as new ones being stolen.

"A link with metal thieves is something worth considering.

"It is good to know that people are using their bikes to get to and fro, but I would like to offer some simple advice to cyclists, to help them to look after their bikes."

Cyclists are advised to securely lock their bikes to a fixed structure even if it is only being left alone for a few minutes.

They should always be locked in well lit areas and near CCTV coverage if possible.

Owners are also advised to mark their bikes with their postcode and house number and keep a photograph to help officers with identification if bikes are recovered.

Cycle theft in Oxford fell by a third last summer after city centre CCTV cameras were trained on bike racks.

However, since then, theft has increased especially in East Oxford.

For more crime advice or to report information about bike theft call police on 08458 505505 or speak anonymously to Crimestoppers on 0800 555 111.