Salary not received since last 4 month

I have been working for an Ltd company in india. Since last couple of months company production is not going good due to some mis-management. Our salary also used to get delayed i.e. instead of 7th it used to come on 10, 12 etc. Each and every time we discussed with management and they said everything will be inline within a month. From December 2015 our salary delayed by month and we were always assured that things will be sorted out in the coming month. Now the situation is that we have not received our salary from last 4 month and we waited for such long because every time our top management including our chairman used to give us time of 1 week or 10 days by when our dues will be cleared and company will start production full fledged. We just believed in their words and case would be our last option. Now the situation is beyond our tolerance limit as every commitment is getting failed and no positive response. We have round about 180+ employee in our unit and out of which 40+ are staff category above 10+ basic. Please guide us to proceed further.