My Inlaws cheated my husband

My husband built a 2 storey house in Chennai in which his parents staying from house warming . My husband was working in USA that time he transferred the money to their account and they built the house worth of less than 35 lakhs., but they got around 56 lakhs to built it. My husband has 2 siblings 1 brother and sister... my Inlaws have 3 more land and they have been agreed mutually and 1 is 2400sqt which has been split into 2 half's and one for my my husband and 1 half for my brother in law and both the sons were mutual agreed to give rest of the lands to their sister... And now they re cheating my husband who built that house... And they send us out and asking us to take our things out as they going to sellook property. As my husband doesn't have any written document of this mutual agreement. But they showed us the stamp paper stating that this house is belongs to my husband and they took the the paper which was not registered yet... Now we took and locked all lands mother documento till we get justice.. suddenly my FIL called Police to house asking for the documents. . He was so panicked and even even the police man said something wrong ... do better keep it with you and bring relatives friends whose about this property and who built everything.... Wat can we do now ? Can we do anything with the mother documents?? How to deal with this ? Help us we got cheated very badly. ...