The Serbian State Lottery has come under fire after the winning ball appeared on screen before it had been drawn from the machine.

Police investigating whether the latest winning lottery combination had been set up in advance have questioned six people since the live broadcast while the game's head announced his resignation.

It happened during the 59th round of the state's lottery on Tuesday evening when the presenter called out the numbers from the yellow balls as they emerged in a clear plastic bowl.

Serbian State Lottery has come under fire after the winning ball - the number 21 - appeared on screen before it was drawn from the machine on Tuesday evening

The first three numbers were called out as normal during the , but there was confusion when the fourth ball was called - the number 27 - the screen displayed it as the number 21.

When the next ball was pulled it was the number 21, leading viewers to question whether the game, known as 'Lotto' in Serbia, had been fixed.

The State Lottery has denied fraud and blamed the incident on a 'technical mistake' with the company head, Aleksandar Vulovic, agreeing to step down out of 'moral obligation.'

When questioned during a television transmission over the regularity of the draw, he said the current situatuon was 'slightly less bad than catastrophic, but still disastrous'.

He added: 'Police and prosecutors will be doing their job. If there was an offence committed, they will respond. For such a breach of trust somebody needs to be held responsible.'

One lottery executive said it was 'pure coincidence' that the graphic would mistakenly call the number 21 ball, only for it then to emerge as the next number.

The number 27 was drawn from the machine first, but the number 21 appeared on the screen before it was drawn next

Interior Minister Nebojsa Stefanovic said five people, including the television hostess, had been interviewed by police and subjected to a lie-detector test.

He said police had seized the lottery equipment.