Reports from Solomon Islands say the regional intervention force has deployed armed officers to an island close to the border with the Papua New Guinea province of Bougainville.
The officers have reportedly been sent to Ovau in the Shortland Islands as a former Bougainville Revolutionary Army commander, Cornelius Galasa, goes on trial in Solomon Islands for a murder in western province.
Prosecutors say Mr Galasa shot dead a Malaitan man, Bobby Nare, in the western provincial capital, Gizo, in June 2000.
Police say criminals in Ovau haven't been acting in response to Mr Galasa's trial, and there's been no comment from RAMSI about its reported deployment.
The chief magistrate of Gizo, Leonard Maina, says many Bougainvilleans have left the Solomons since 2000.
Mr Maina says intervention force police have been keeping control.
"There is no ethnic tension at the moment, and the authorities are in Shortland at the moment and also in Gizo, RAMSI's doing a very fine job in this part of the country."
Mr Maina says now there are very few Bougainvilleans in Solomon Islands.