Is collector has rites to take back assigned lands which has 1B also ?

Hello Sir, My father had 5 acrs of assigned land (DKP) from 45 yrs. He had 1B also. In august he died. The property got transferred to my Mother's name and she got 1B. Now my uncle (My father's own brother) is demanding money else he is ready to go to Collector to request for cancelling the property. He is going to Collector along with local political leaders to tell that she (My mother) is not poor so pls take back the property and give to me. Is it possible ?