Zagreb County Court investigating judge Jadranka Mandusic on Wednesday decided on remanding the three suspects in investigative custody for one month.
Kolar, 61, a former long-standing HSS parliamentarian, is suspected of having abused his office while being at the helm of Molve.
Tos, 54, is suspected of having incited him to commit crime.
Kolar was arrested at his house in Molve, northern Croatia, on Tuesday morning. He was at the helm of that municipality until the last local election when Stjepan Fosic of the Croatian Democratic Union (HDZ) won the polls.