Holding asset after getting Terminated(Disciplinary Action)

So I was terminated citing leaves and performance issues on November 7th. I don't fully agree to their allegations, both in terms of leaves and performance. It has been a one sided decision with not much objectivity. Moreover, my salary for October still remians unpaid - work that is already done. And I am now told that it will given in Full & Final Settlement after I hand over company's assets. I know for a fact, that once I return the asset(laptop), they will cite numerous deductions and I won't get back anything. The salary was due on 31st October and I wasn't terminated then, do they have the power to push that due salary to F&F. On asking them the F&F amount that I will be getting on email, and to confirm the number, they are denying to quote unless the asset is handed over first. And they are threatening with lodging an FIR if I don't immediately return the asset. I have made my intentions clear in all mail communications that I intend to return the assets, and I am holding the asset in lieu of my unpaid salary. What is the best option for me wherein I can get my October salary and they get their laptop?