Top Gear could be heading for more trouble after communications watchdog Ofcom confirmed it was investigating a complaint over the use of the word "pikey".

A representative of the Traveller Movement complained after a scene in which the show's now ex-host Jeremy Clarkson was seen holding a placard with the words 'Pikey's Peak' while Richard Hammond drove a car up a mountain.

It comes after a similar complaint was lodged with the BBC but eventually not upheld.

The BBC Trust ruling in March cleared Clarkson of racism and its editorial standards committee (ESC) concluded the word had been used to mean "cheap", rather than as a term of racist or ethnic abuse.

Speaking at the time, a spokesman for the Traveller Movement said they were "horrified" by the "BBC's green-lighting of the use of the word",

It is not the first time the controversial motoring show - and its former presenters - have run into trouble.

Clarkson had to apologise when unscreened footage emerged of him mumbling the n-word while reciting the children's nursery rhyme "eeny, meeny, miny, moe" to choose between two cars and the show was also censured by Ofcom for breaching broadcasting rules after Clarkson used a "racial" term during the programme's Burma special.

Last year ended with the motoring show's crew forced to flee Argentina when it emerged they were using a Porsche with the registration number H982 FKL, which some people suggested could refer to the Falklands conflict of 1982.

Since then, Clarkson has left the show when the BBC allowed his contract to run down after an internal investigation found he attacked show producer Oisin Tymon in an unprovoked assault.

His co-stars, Hammond and James May, are believed to have also left the show, along with producer Andy Wilman, and are expected to launch a rival show with another broadcaster.

A spokesman for the Traveller Movement welcomed the decision to investigate.

He said: "When the BBC Trust ruled that the Top Gear use of the word 'pikey' had nothing to do with gypsies and travellers and meant cheap and dodgy instead, it was clearly the trust that was being a bit cheap and dodgy.

"We believe in freedom of speech, but with that freedom there must be responsibility. The BBC Trust abdicated that responsibility when they legitimised the use of a racist word on one of their most popular and money-spinning programmes.

"We can bang on about semantics and meanings but at the end of the day too many gypsies and travellers hear that word in the form of racist abuse.

"How can you work for understanding and integration when racist abuse is seen as funny by a national public broadcaster paid for by the public?

"We hope that the Ofcom investigation is thorough. This is clearly a topic that needs some attention, particularly with the often-mocking and derogatory TV fascination with all things gypsy."