Assualt against my father when he stopped his bike when an old couple fell on the road

An old couple were crossing the road. My father (is a farmer)saw them falling in the middle of the road while riding the bike and inorder not to hit them,he applied the break and stopped his bike. the bike didn't even touch them.still the women called his grand children and their freinds..one of them hit my dad while he was explaining what happened there.a vehicle driver saw all this and even said to them that the old couple were fell on their own and the bike didnt touch them.mean while my father felt pain in his chest and was taken to hospital.the constables suggested not to give any complaint on that day even though my whole family suggested it badly.but now the old couple demand 35000..one of the constables and asi without any enquiry forcing us to pay the money. There works a relative of the old couple in police station (not at all related to the police dept.). He is known for bringing fault accused cases and demand money from innocent people.when my cousin asked him about the women he said she got her blood clot removed and went home.but he started lying she was I'll. the constable even lied that the asi and another constable went for an enquiry ..we came to know that was a lie when we asked the other constable about it. The asi didn't even listened to the friend of the old couple grandson,where he said what the vehicle driver who witnessed all this said. they are pressuring to pay 35000 from my dad.all this made my father depressed and he now facing health issues..can anyone out there please suggest us how to deal with this injustice?