Fiji police are reported to be closing in on who gave the order for the removal of President Mara from office during the May 2000 coup.
The Fiji Sun reports that this has been confirmed by the police spokesman, Mesake Koroi.
Mr Koroi is quoted as saying that investigations were to have been completed next month but are now expected to take longer.
The former president was asked to step down by a group of senior figures who included the then police commissioner Col Isikia Savua, the military commander Commodore Frank Bainimarama, the former prime minister Sitiveni Rabuka and the current chairman of the Great Council of Chiefs, Ratu Epeli Ganilau.
Goerge Speight and his men, who were holding hostages in parliament, had demanded President Mara's removal and at one stage sent rebel gunmen to fire at Government House.
Fiji's opposition leader, Mick Beddoes, says the police should lay charges quickly.
Mr Beddoes says police should also work in earnest on those who planned and carried out the coup and those businesspeople who funded it.