Yes you are correct as for a police action( as in stopping a crime in progress). This, according to BLM, is a court action requiring asset forfeiture and contracts. This court action would be a Marshal assignment which is the enforcement arm of the court. Not BLM.
In my opinion we need to get after congress to start an investigation of this matter. Who authorized it, why was it such a total mess, was it legal. At the very least someone needs to lose their job and the best outcome would be to have BLM funding cut in half until they figure out what their mission is. It is NOT government land, it belongs to the American citizens.