A senior police officer responsible for protecting children online hit out at some of the world’s leading social networking sites.

Jim Gamble, head of the Child Exploitation and Online Protection (Ceop) Centre, said Facebook and MySpace could do more to keep youngsters safe.

He said he was disappointed the two internet giants have not adopted a panic button for children who fear they are at risk.

His comments came after their competitor Bebo, now owned by AOL, adopted the “Ceop report” button.

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The button enables users to report online abuse, bullying and illegal activity as well as offering advice about hacking and viruses.

It was launched just a day after charity Beatbullying pinpointed Bebo and Microsoft’s instant messaging service as hotspots for bullying.

The charity polled 2,094 young people across England and found nearly a third (30%) of 11 to 16-year-olds who had been “cyberbullied” had been targeted on Bebo.

Mr Gamble said there is “no legitimate reason” for refusing to put the button on a website.

He said: “I do not want my criticism to be taken as a swipe at the online industry. The vast majority of players are doing a good job and doing their best to make the environment safe.

“This is aimed specifically at social networking sites. They are creating a public space that attracts young people, children and adults, so they can make money through advertising.

“We applaud that but do not forget while you do that there is a responsibility, a duty of care, to the young and the vulnerable.

“We are here to help at a low cost, in fact, this is free, we are giving away this service. What cost can you put on child protection? I have seen the horrible aftermath of it.”

Mr Gamble said some sites claimed technical issues block the button while others suggest companies do not want to lose a potentially-lucrative advertising space.

He added: “It is tiny and does not take up any significant real estate. The bottom line is there is no legitimate reason for not taking it and placing it on a site.”

The Ceop report button allows computer users to report fears directly to the Ceop Centre in central London.

There are also links to 10 other sources of help including Childline and charity Beatbullying.

Up to 10,000 people are already pressing the button every month through other online services.

But there appeared to be some teething problems on Bebo yesterday, with users pressing the Ceop report button receiving a security warning.

The automatic reply said the button connected to an invalid link probably set by fraudsters attempting to steal personal details.

Sir Hugh Orde, president of Association of Chief Police Officers (Acpo), joined the call for other websites to adopt the button.

A Facebook spokesman said: “The safety of Facebook users is the top priority for the company, which is why we have invested in the most robust reporting system to support our 300 million users.

“We also work closely with police forces in the UK and around the world to create a safe environment. Our teams are manned by trained staff in two continents giving 24-hour support in 70 languages.

“We are constantly looking to strengthen our procedures further and are in dialogue with Ceop on this and a range of other issues.

“We look forward to hearing about the experience of Bebo using the Ceop button and will take account of their experience in any future evaluation of our reporting systems.”