THE number of calls to Avon and Somerset police which involved social networking website Facebook has gone up by more than 2,000 in the last two years.

And the force has revealed that there were nearly 80 occasions when the site was used to solve crimes.

Callers last year mentioned the internet site 11 times more often than in 2008 but the site has also been used to help solve crimes.

According to figures released in a freedom of information act request the force handled 3,179 calls – both 999 and non-emergency – in 2010 where the word Facebook was mentioned.

This is an increase of more than 1,000 per cent from 2008 where just 271 instances were recorded. The number has risen dramatically with 1,432 callers mentioning Facebook in 2009.

It is thought that the data does not just represent crimes involving the site, but also where it has been mentioned within the context of a call, for example to report an unrelated crime or when giving information.

Avon and Somerset Police has its own Facebook page and said the site has been used as a tool to raise awareness of missing person appeals.

It said there was no policy within the force to advise the use of the page for crime fighting but revealed there were 79 instances where Facebook was used to solve crimes during the last three years.

During the investigation surrounding the murder of Clifton landscape architect Joanna Yeates' in January this year officers were understood to have used information from the 25-year-old's Facebook page to carry out inquiries.

It also launched an appeal for more information through the site saying it was "far more cost-effective" than poster campaigns and mass leaflet distribution.

But it has also warned people to be vigilant online, especially when giving out personal information.

Last year photos of pupils at a South Gloucestershire school were found on a computer belonging to a suspected paedophile.

Children at Marlwood School in Alveston were warned to change security settings on social network internet sites after the discovery.

Police suggested the man may have gained access to the photos by being a Facebook "friend" with a pupil.

The Child Exploitation and Online Protection Centre (CEOP) also offers young people advice on how to stay safe online on its own Facebook page. It also recently launched a film, called Exposed, that looks at the dangers young people face when sending images of themselves to each other.

A CEOP spokeswoman said: "The internet opens up the world to all young people and even more so for those who are especially vulnerable, allowing them to connect with friends and family in ways they can't in the real world. We have been working with, and will continue to work with, Facebook to ensure their users are as safe as they can be when online."

The spokeswoman said young people should consider the personal information they put online – and mobile phone numbers, school names or home addresses should not be posted. She added that the same care should be taken when posting photographs on the internet.