I was buying a house worth about 45 Lakhs. I paid 10 Lakhs upfront and agreed to pay the rest after receiving the property papers. But after 15 days, the seller took my remaining 10 Lakhs and disappeared. What should I do now?

You should immediately file a police complaint alleging cheating and breach of contract. You can also file a civil suit for recovery of the remaining amount and seek specific performance of the agreement, compelling the seller to handover the property papers.