The Solomon Islands National Peace Council says its monitors report members of a police team on the Weather Coast of Guadalcanal have been using weapons to threaten and initimidate civilians.
The team is on the coast officially to pursue rebel leader Harold Keke.
The guns being used had been among those in the police armoury in Honiara surrendered during an 18 month gun amnesty that finished in May last year.
The Chairman of the Peace Council, Paul Tovua, says they were expecting the guns to be destroyed.
"Our concern is that for peace to come back throughout Solomon Islands we need all the guns to be returned or destroyed so that there will be no threat, intimidation or killing by the use of guns and such weapons."