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.
Superintendent Gideon Kadi of Gizo police says criminals in Ovau haven't been acting in response to Mr Galasa's trial.
"We have a small incident down in Ovau at the weekend. That was an isolated problem I think that was a criminal activities, it's nothing to do with Cornelius incident. I'm not sure that there had been soldiers sent down there. I'm not certain about that."
Superintendent Kadi confirms that fighters crossing from Bougainville have threatened security in the western Solomons before.
There has been no comment from RAMSI about the reported deployment