Employer is not giving the PF account number and they are unnecessarily delaying it

I want to know my PF account number, as i have worked in a previous company and leaved the company after 1 year of service .Now the problem is ,employer is not giving the PF account number and they are unnecessarily delaying it and even i asked them many times they are not providing it. Is there any other way to know the PF account number so that i can withdraw the money or i can tranfer the previous PF number to the current orgainisation.

Dear Garubalaji,
This has with reference to your query kindly confirm, do you have any proof for monthly PF deduction... such as pay slip, salary annexure or salary bifurcation statement may be received along with appointment letter at the time of joining or any clause regarding EPF deduction / contribution mentioned in your appointment letter.