An investigation has been ordered in Bulgaria after the same six numbers were drawn in two consecutive rounds of the national lottery.
The numbers - 4, 15, 23, 24, 35 and 42 - were chosen by a machine live on television on 6 and 10 September.
Saying that manipulation was impossible, the lottery organisers described it as a freak coincidence, and pointed out that on each occasion the numbers were drawn in a different order.
A mathematician said that the chance of the same six numbers coming up twice in a row was one in four million. He also said that coincidences do happen.
Physical Education and Sport Minister Svilen Neykov said the commission established to investigate would provide answers towards the end of the week.
Nobody won the top prize in the first draw, but a record 18 people guessed all six numbers in the second draw. Each won $10,000.