Tongan police have charged a member of parliament and a local businesswoman who were allegedly ringleaders in the November riot which left seven dead and destroyed much of the capital's centre.
The acting police commander, Taniela Faletau, says pro-democracy lawmaker, Isileli Pulu, has been charged with sedition and abetting wilful damage to property.
A businesswoman, Ofa Simiki, was also arrested this week and charged with sedition and abetting arson.
A total of 678 people - ranging in age from nine to 70 - have so far been arrested on charges related to the riot, which destroyed around 80 per cent of Nuku'alofa's central business district.
The commander pleaded for patience over public demands for the arrest of prominent people who were visibly involved in the riot.
The frenzy of burning and looting on November 16 destroyed 66 buildings in the heart of Nuku'alofa.
It followed a protest against the slow progress in reforming the semi-feudal political system in Polynesia's last monarchy