IT data seized from Fifa headquarters
Fifa has handed over computer data to the Swiss authorities investigating the World Cup bids for 2018 and 2022.
The information was seized at the Zurich headquarters of world football's governing body from offices which included that of its president Sepp Blatter, the BBC understands.
Fifa said it had co-operated fully with the authorities.
Swiss police said last month that they were looking into how the forthcoming World Cups were allocated.
The US Federal Bureau of Investigation (FBI) is also carrying out an investigation into corruption at Fifa. So far 14 people have been indicted, nine of whom are current or former Fifa officials.
IT data from the offices of secretary general Jerome Valcke and the organisation's financial chief Markus Kattner is also believed to have been released to Swiss police.
Fifa reiterated that it had instigated the inquiry and the organisation was, according to the Swiss Attorney General, the "injured party".
The criminal investigation focuses on the mismanagement of funds in relation to the 2018 World Cup in Russia and the 2022 tournament in Qatar.
Both countries have denied any wrongdoing.
The bidding process for the 2026 World Cup has been postponed. Valcke said on Wednesday that it was "a nonsense" to begin the process in the current climate.
Blatter has announced he will step down from his role as president, amid the ongoing allegations.
He is expected to be replaced at an election on 16 December.
Former Brazil midfielder Zico announced on Wednesday that he intends to try to stand for the presidency.
The-52-year-old, whose full name is Arthur Antunes Coimbra, will be regarded as an outsider for the job, correspondents say.