Regarding a couple who fled from home

Sir there is a muslim boy who is my friend. Few days ago he(age 22yrs) left his house from Amethi with a hindu thakur girl who is under 18yrs on school certificates but actually 20yrs old. From Amethi he planned to go to Surat via Patna. they both hadn't taken their meal during the journey so they contacted me on phone in patna where i am currently pursuing by B.tech and told me that they have run from home , and asked me to bring food and some medicine for his girlfriend. I met him on Patna junction with some food and suggested him train to go to Surat as I was unaware of the rules regarding helping people who ran from home. The boy left for Surat and now he is not in contact with me or any of his relatives for past 1 week.The case is with Amethi police. They are knowing about by involvement in it and are thinking that i have given shelter to them to hide ,and as they have been unable to find the boy they are threatening me on phone and saying to arrest and torture me and my family if i don't bring that couple back.kindly suggest me what should i do in this situation. and if i am proved guilty in court what punishment i can get