Mr Hickey was questioned for several hours last night
The President of the Olympic Council of Ireland has been denied bail in Brazil.
Reuters report Pat Hickey has now been taken to a maximum security prison, believed to be Bangu Prison, in Rio de Janeiro.
Mr Hickey was questioned by Brazilian police for several hours last night, after being discharged from Samaritano Hospital.
He had complained of chest pains following his arrest on Wednesday.
The 71-year-old has temporarily stepped down as OCI president as the investigation continues.
Sports Minister Shane Ross is meeting with the Attorney-General Máire Whelan over what type of inquiry to set up into the controversy.