Previous Employer Threatens

Hi, Currently I am going through a very difficult situation. I had been working in a firm X since last 11 months. While joining the company ,the employer had told me that they will give me a hike after six months. So I joined this firm with out getting any increment on my salary. But I didn't get any increment even after 11 months. Now I got a better job from another company. So I have informed my employer that I want to shift the job. Then my employer had asked me to serve a notice period of three months .And he threatened me saying that I will regret for leaving the firm. But the notice period was not specified in my joining letter and I have never signed any contract to serve 3 month notice period also. I talked to my new employer to give me some more time and they gave me 45 days time. So I served a notice period of 45 days and then left the firm X. BUT NOW FIRM X IS THREATENING ME SAYING THAT THEY ARE GOING TO FILE A POLICE CASE AGAINST ME FOR LEAKING THEIR SOFTWARE. THEY HAVE CALLED MY CURRENT EMPLOYER AND TOLD THE SAME. What should I do now? I have never done any frauds. And my previous employer is person who has worked on big MNC s and he has a lot of contacts also. I am really scared and don't know what to do now. Please help me with your valuable suggestions