Pictured: Roger McNamee, who invested in Facebook in its infancy, said he feared the tech giants were not being held accountable

Facebook officials have been compared to the Nazi propaganda chief Joseph Goebbels by a former investor.

Roger McNamee also likened the company's methods to those of Edward Bernays, the 'father of public' relations who promoted smoking for women.

Nr McNamee, who made a fortune backing the social network in its infancy, has spoken out about his concern about the techniques the tech giants use to engage users and advertisers.

Speaking in Washington, the former investor said everyone was now 'in one degree or another addicted' to the site while he feared the platform was causing people to swap real relationships for phoney ones.

And he likened the techniques of the techniques of the company to Mr Bernays and Hitler's public relations minister.

'In order to maintain your attention they have taken all the techniques of Edward Bernays and Joseph Goebbels, and all of the other people from the world of persuasion, and all the big ad agencies, and they've mapped it onto an all day product with highly personalised information in order to addict you,' Mr McNamee told The Telegraph.

Mr McNamee said Facebook was creating a culture of 'fear and anger'. 'We have lowered the civil discourse, people have become less civil to each other,' he said.

Mr McNamee said the tech giant had 'weaponised' the First Amendment to 'essentially absolve themselves of responsibility'. He added: 'I say this as somebody who was there at the beginning.'

Mr McNamee he likened the techniques of Facebook to Hitler's propaganda agent Joseph Goebbels

Mr McNamee's comments come as a further blow to Facebook as just last month former employee Justin Rosenstein spoke out about his concerns.

Mr Rosenstein, the Facebook engineer who built a prototype of the network's 'like' button, called the creation the 'bright dings of pseudo-pleasure'.

He said he was forced to limit his own use of the social network because he was worried about the impact it had on him.

He said it was 'very common for humans to develop things with the best of intentions and for them to have unintended, negative consequences'.

Facebook is expected to see a decline in usage among teenagers in the US this year, according to experts.

The market research company eMarketer has predicted 14.5 million people aged between 12 and 17 will use it in 2017, down 3.4 per cent from the previous year.