A brief reflection of light made some players think a ball in last night's Lotto Plus 1 draw had two different numbers on it, the National Lottery said this afternoon, as it moved to assure players of the integrity of the draw.

A picture shared on social media appeared to show the number 38 ball also had the number 33 on it when it was drawn last night.

A statement from the lottery this afternoon said: "A brief reflection of light during filming caused an illusion and some players to think there were two numbers on ball 38. This was not the case.

"The weight and size of all Lotto balls, and the numbers, are strictly checked in advance of each draw.

"This process, as well as the draw itself, is independently observed by our auditors KPMG."