Image caption The game show, presented by Ant and Dec, began its run on Saturday

Three contestants from ITV1 game show Red or Black? have been dropped after producers tightened checks on those taking part.

The move comes after the £1m top prize was won on Saturday by a man from Reading, who was revealed to have a conviction for assault.

The remaining programmes will go ahead, but some episodes will have a reduced number of contestants.

The show, presented by duo Ant and Dec, is running all this week on ITV1.

ITV had initially announced on Wednesday afternoon that two contestants would be dropped from the show, however a third was pulled from Wednesday night's show just before broadcast.

The programme was the first to air with seven, rather than eight contestants.

Earlier, an ITV spokesman had said: "ITV has reviewed the background checks on remaining contestants from Red or Black?

I'm not sure that production companies will routinely do criminal records checks Medwyn Jones, Harbottle and Lewis

"As a result of this we have asked producers to remove two contestants from this week's shows."

Red Or Black? is a co-production between ITV Studios and Simon Cowell's production company, Syco.

The spokesman said all parties were "working closely and collaboratively together to ensure that the show continues its success".

Nathan Hageman, 31, won the first £1m prize on the first show on Saturday.

Yet ITV came under pressure to strip him of his winnings when his conviction came to light.

The bricklayer was initially reported to have been jailed for attacking a man. It was later disclosed he had in fact attacked a woman.

In an earlier statement, ITV said producers had made "thorough inquiries" into Mr Hageman's participation in the show.

'Checks in place'

"Whilst producers were aware that Nathan had served a prison sentence for assault they were not fully aware of facts which have since emerged.

"As a result of this ITV is reviewing the background checks on all remaining contestants in the show."

When the show was launched in May, presenter Ant McPartlin said there would be checks in place to ensure winners were "not going to be criminals".

Image caption The show is co-produced by Simon Cowell's company Syco

At the same event, Cowell said the show was likely to feature "all types".

Asked how show bosses would make sure there was a worthy winner, McPartlin said: "All the checks will be in place so they're not going to be criminals.

"But when you randomly select people, who knows? I don't think we should discriminate at all."

Medwyn Jones, a partner at media law firm Harbottle and Lewis, told the BBC that most TV game shows require contestants to declare criminal convictions.

"Most contributor releases will have clauses in them under which they confirm that they don't have criminal convictions, and they are not connected with anybody involved in the production of the show or with the broadcaster.

"But I'm not sure that production companies will routinely do criminal records checks," he said.