The government has been urged to create an independent regulator to tackle harmful and illegal content on social media.

A committee of MPs chaired by the Folkestone and Hythe MP Damian Collins has issued a report heavily criticising social media companies for their inaction.

The all-party select committee on media says in a major report more action needed to be taken to tackle concerns over unregulated content on social media sites.

Pressure is mounting for regulation on the issue of harmful content following the death of teenager Molly Russell.

Her father accused Facebook-owned Instagram of facilitating her death, by failing to remove images of self-harm.

MPs also want a new code of ethics and, if they are breached, powers to impose large fines.

Damian Collins said social media companies needed to take responsibility for what was on their sites.

“The big concern for us is that tech companies time and time again fail to act on harmful content that should not be there,” he said.

"It is not enough for social media companies just to apologise and there should be legal powers to censure and fine them," he added.

"The tech companies seem to think they are a law unto themselves..." Damian Collins

The report also highlights concerns about social media sites and electoral campaigning with data being used by political groups without the knowledge or consent of individuals they were targeting.

“There is often no transparency of who is the messenger or advertiser is and that must end too," said Mr Collins in an interview with Sky News.

“People have the right to know when they are sent political communications who is behind it. The tech companies seem to think they are a law unto themselves and actually laws are made by parliament and other industries are regulated; we want to see harmful content removed and they are best placed to do it.”

He also criticised Mark Zuckerberg, the founder of Facebook, saying that he failed to take responsibility and did not act as a leader of one of the world's biggest companies.

“It is time he stopped hiding behind his own Facebook page,” he said.

The report’s recommendations come the week after an independent review into the future of UK news recently recommended that a regulator should oversee Google and Facebook to ensure their news content was trustworthy.