The raids, on hotel rooms and offices in Rio, follow last week's arrest of Pat Hickey, head of the Olympic Council of Ireland and member of the International Olympic Committee. The 71-year-old is being held in a Rio prison, pending formal charges.
The Olympic Council of Ireland (OCI) said police had met some of its officials during the raids and asked them to appear at a police station for questioning on Tuesday. None of the officials were arrested, the OCI added.
Those who had their passports seized on Sunday morning were OCI Executive Director Stephen Martin, Secretary-General Dermot Henihan and Treasurer Kevin Kilty, police said.
A Brazilian judge also ordered the seizure of the passport of stand-in OCI president Willie O'Brien, senior vice-president John Delaney, and an OCI personal assistant, Linda O'Reilly.
A police source had earlier said that O'Brien's passport had been seized, but a statement from a Brazilian court later said it was being sought.
Rio civil police said in a statement they had started an operation on Sunday linked to their probe into an international ticket touting ring, but declined to provide further details.
Police allege Hickey is implicated in a scam involving Ireland's official Games ticket reseller, Dublin-based PRO10 Sports Management, and an international sports hospitality company, THG Sports.
They accuse PRO10 of funnelling tickets to THG Sports, which sold them illegally at inflated prices. A director of THG Sports, Kevin Mallon, was arrested this month in Brazil.
PRO10 and THG have denied wrongdoing. Hickey's lawyer in Dublin did not respond to an email from Reuters.
Police say they seized more than 1,000 tickets from THG Sports, which is not an official ticket reseller, and a judge has ordered the arrest of four more THG executives on accusations of fraudulent ticket sales at the Olympics.
THG has said the seized tickets were being held legally on behalf of PRO10.
Police say they have also issued arrest warrants for three PRO10 executives.
Hickey is expected to appear before a judge on Tuesday, the IOC said on Sunday.
(Additional reporting by Karolos Grohmann and Pedro Fonseca; Editing by Mark Bendeich and Alison Williams)
