Three army personnel in civvies and travelling in a white van with fake number plate were arrested last night in Mirihana, Police said.
They said a weapon was also recovered from their possession.
The army personnel had informed the Police that they were from the security detail attached of an Army Major General.
Police are in contact with the Military Police to verify whether it was really so.
Meanwhile, issuing a statement, the Army said the Military police has launched a probe into the incident. They said action would be taken against the soldiers if found guilty.