Ricky Gervais comes under fire from disability groups after jokes on Twitter

The 50-year-old star of The Office had written messages on Twitter saying things like 'Good monging'.

The word mongol used to be an offensive and derogatory word used as an insult against those with Down's Syndrome but Gervais claims the meaning of the word has now changed.

According to UK newspaper The Sun, Mark Gale, from Mencap, said: 'It's very disappointing. Such language can perpetuate discriminatory attitudes.'

Frank Buckley, from Down Syndrome Education International, added: 'Most would consider it as offensive as comparable terms of abuse referring to racial background or sexual orientation.'

However Gervais said it was not meant that way.

He said: 'I have never used the word Mongol. I have used 'mong', but never to mean Down Syndrome and never would.

'The meaning of words change over time - 'gay' for example. The modern use of the word 'mong' means dopey or ignorant - it's in slang and urban dictionaries.'