There is tension in Tonga following the destruction of property at two government ministries overnight.
Four government vehicles were set on fire outside the tax and customs department and the head office of the Ministry of Education was stoned and windows smashed.
There have been no arrests relating to either incident.
Public servants, who have been striking for nearly five weeks calling far wage increases, have denied any connection with the events.
Our correspondent, Mateni Tapueluelu, says there is now an increased police presence in and around the capital, Nuku'alofa.
"The Tonga High School was guarded by police. The residence of the ministers are being patrolled as well. The BP and the Shell Oil Station, here in Tonga they are located together, were guarded last night as well as the airport."
The two incidents follow the arrest of 15 students for allegedly vandalising equipment at their school in protest at disciplinary action against staff for strike related matters.
Meanwhile, Britain and Australia have updated their advice to tourists wanting to travel to Tonga.
Britain's Foreign and Commonwealth Office says levels of robbery, theft and violent assault have recently increased in Tonga and security risks increase after dark.
Australia's Department of Foreign Affairs and Trade says tourists in Tonga are advised to exercise good personal security awareness