Tonga's capital Nuku'alofa has been hit by riots after pro-democracy groups protested against a government delay in implementing political reforms.
The government offices were set on fire
Rioters smashed windows in the prime minister's office and other government buildings and overturned cars.
Calls for more democracy have grown over the last year, and were fanned by the old king's death in September.
The South Pacific nation's king and hereditary noblemen hold the majority of seats in the country's parliament.
The rioting began after the government assembly failed to pass democratic reforms before it rises for the year later on Thursday, Radio New Zealand International said.
Demand for reforms
Thousands of pro-democracy supporters were demanding that a vote on a new democratic constitution be held this year.
"People threw stones at the prime minister's office," said the RNZI reporter in Nuku'alofa.
"They turned over police vehicles and vehicles of the prime minister's office," said Mateni Tapueluelu.
"They have also done the same to a supermarket owned by the prime minister and there are men marching to the villa where the king is supposed to be residing."
Shop staff were unable to prevent looting
Pro-democracy demonstrations last year culminated in a series of strikes that brought the capital Nuku'alofa to a standstill.
A government committee was set up to examine reforms.
After the death of King Taufa'ahau Tupou IV in September, it recommended that that all lawmakers be elected by the public, rather than appointed by nobles or the king.
King Tupou IV reigned for 41 years and was opposed to reforms.
His son and heir, Siaosi Tupou V, is thought to be more in favour of change.