Absconded from company

i was working for Level 5 IT company,i resigned from there with immediate effect and stop going to office.now i received registered speed post form company and also mail stating serve ur notice period or pay the amount.same was also mentioned in offer letter.now i want to know how far can company go to chase me in this case.i left company for masters studies.worked there for 3 month.i have 3 year of exp.

i was working for Level 5 IT company,i resigned from there with immediate effect and stop going to office.now i received registered speed post form company and also mail stating serve ur notice period or pay the amount.same was also mentioned in offer letter.now i want to know how far can company go to chase me in this case.i left company for masters studies.worked there for 3 month.i have 3 year of exp.

I was working with an IT company for past 4 months. The work culture there was pathetic and they tortured me a lot. Due to which i kept on losing my self confidence and decided to abscond the org. although i didnt sign any legal document from the org regarding money given on not serving notice period. I submitted my resignation letter after 2 days in which i clearly mentioned that I will not be able to continue due to my health issues and will not be able to serve the notice period. and now they are threatning me and asking to serve the notice period for 2 months or give them medical proofs of my illness which i know they will not approve or give them the amount for 2 months of notice period or they will take legal action against me. What should i do in this case,I do not want any relieving letter from the org and neither i ever wish to work there.

will they file any case against me?