Hindu family land dispute

My grandfather had some 52 dismil land (fully owned) in karmatand,DHANBAD, Jharkhand area. B.C.C.L ( gov coal company) bought the land from us in exchange of a government job in B.C.C.L. So,my grandfather had 4 sons,the elder one went ahead and claimed the job. My name is Sunny Kumar,I am the son of the 3rd eldest brother. Now,We had another 10 dismil land. Grandfather leased it from the government for farming purposes but later we settled on it and built our houses on it which is our current home as my grandfather got job and left farming completely. The elder one left the home and the jobless brothers and settled in a B.C.C.L residence offered by them. Now after 35 years, the elder brother has returned back to claim on this 10 dismil of land which rest of the 3 brothers share to build houses for his sons. does he have any claim to the land? as he has already taken share of 52 dismil land before as he got a government job because of it. Elder brother has 3 sons and are committed to physical violence and threatening us if we don't offer them the desired space in left land. They have already started building house . Does he has the right over land ? He already had his share in form of job by sale of our 52dismil land Can I take any legal action?Should I contact Panchayat?Police?. Please reply asap matters are tense