Advice in case employer forcing to leave job without any notice

A few day ago my company (pvt ltd.)asked me to leave or put the papers of resignation on immediate effect. There was no poor performance matter also and not even got any warning from managment in my earlier days also. I have given 10 years to this company and was working efficiently.suddenly they took this decision and I was shocked and stucked in between and feeling harassed. Also they are saying I will get only one month pay as notice period. Getting another job at this moment is tough I was single source to earn money , I have not sent any mail for resignation yet but they repeatedly asking me to do that. What should I do kindly suggest, is any case can be applied on them.