My salary isn't paid

Hello, In 16th December of 2014 I was hired as a web designer position for an IT company in Kolkata. I have the joining later which they send into my email account. last month 19th January the owner told me my performance is not good enough to work here and told me to leave now the office. I was quite surprise about that incident because I think that reason was quite unfair and it's driven by his personal grudge. Anyway, before I left the office One senior guy of HR department told me that he will called me in evening and let me know their decision for keeping me or not moreover, when I asked for my salary he told me he will also talk about that matter in evening. However till today I didn't get any call from them. Several times I try to talk with HR department but most of time they are too busy and assure me they will call me later, which was never happened. Luckily one day i am able to catch that senior HR guy over the phone and he told me to call yesterday after 6 pm. As usual I called the office they said he is busy in a meeting. So today I call again and finally can talk with him and he said that GM told him though my performance was not good enough therefore I am not eligible for salary. I told him I worked there for eight hours everyday, even sometimes i stay more than my normal job hours and I did one day overtime as well. So why I am not getting my salary? After hearing that,he told me he will be talking with GM again and he will let me know. Now I am getting worried about that because I have no faith on there following up procedure and I am quite sure that they don't want to pay my salary. Please help me and tell me what should i do. Thank You. Abhijit Das