Passports of foreigners working in India hired by an Indian company

I WOULD LIKE TO KNOW WHETHER AN INDIAN COMPANY HIRING FOREIGN NATIONALS TO WORK IN INDIA, ARE THE PASSPORTS OF THE EXPAT EMPLOYEES BE KEPT UNDER THE SAFE CUSTODY OF THE EMPLOYER TILL THE CONTRACT PERIOD IS COMPLETED. IS IT LEGALLY RIGHT . IF NOT WHAT IS THE ALTERNATIVE FOR THE EMPLOYER TO HOLD THE EXPAT IN HIS COMPANY TILL THE CONTRACT PERIOD IS COMPLETED. PLEASE CLARIFY