Tonga has appointed a new deputy prime minister, James Cocker.
A government statement says Mr Cocker will take over the duties of the police minister, Clive Edwards.
Mr Edwards and two other cabinet ministers were sacked earlier this week.
The dismissals are reported to be fall-out from a row between the prime minister, Crown Prince Ulukalala Lavaka Ata, and his elder brother, the heir to the throne, over rival domestic airlines.
Each prince had backed a different airline to provide domestic services, after the collapse of Royal Tongan Airlines earlier this year.
In a statement issued late on Friday night, the government says the prime minister will complete what it describes as a ministerial reshuffling over the next few weeks.
A reporter in Tonga, Mateni Tapueluelu, from the Taimi o Tonga newspaper, says the sacked ministers are considering court action over their dismissals.