Tenant destroyed property in my absence

You assess the damages caused by him in terms of money and send him a legal demand notice demanding the costs towards the damages, if he is not responding or not complying with the demands made, you may file a money recovery suit in the civil court

The rented and damaged property is stated to have been vacated and handed over 18 months before, what were you doing during this period ? It implies, either there was no damage when you took over the premises and it is a fabricated alllegation or you have accepted / condoned the damage.

Get the damage repaired at your own cost, the earstwhile tenant is out of your reach to accept your claim / version.