The French administration of Wallis and Futuna has condemned attacks on its premises.
An complaint has been lodged with the police after the office complex in Mata Utu was stoned and windows were broken.
The prefect said if the investigation showed that this event was linked to ongoing strikes, incomprehension would be added to indignation.
He said this would not reflect the spirit of the dialogue in place since the industrial conflict started.
Jean-Francis Treffel said there had been some 50 hours of negotiations so far.
Some public servants and firefighters have been on strike since October in part to be back demands to be integrated into the French public service.