This situation will fall under Trespass, and this is actionable, and the plaintiff doesn't have prove the damage caused by action of trespass.
The police officers, if they were called to arrest the trespasser(s), and they decided to look at, or ask for certain documents, it is an act of misfeasance, and if they are omitting to do the actual lawful purpose, it is considered nonfeasance.
There are remedies-
You can use REASONABLE force to get the trespasser(s) out of the land.
Under Section 6, specific relief Act, you can also file a suit to get the trespasser(s) evicted.
Hope this helped.