If college as lost original certificates of the employee

Hi sir, I am a one of the teaching faculty, had submitted my original certificates (Degree certificates) to my college at the time of joining. It has been mentioned in the appointment letter that probationary period was one year. After a year they were not given any kind of extension letter or confirmation letter, now I have completed 3.5 yrs of service in the same college without any Break… After two years Principal informed me that at the time of Xerox they have lost my certificates and marks cards and pressurized me to bring the original certificates from the University. After refusing, they filed a complaint in local police station and gave the complaint copy and an affidavit and forcing me to bring the documents from the University. In replay of that letter, I asked why only my documents were missed while Xeroxing, and asked them to mention who and why they took the documents for the Xerox. Till now they simply ignoring the further corresponding and every time pressuring me to bring the duplicate copy of the originals from the university by giving job threaten. Kindly suggest what I should do to get them back and what compensation I can ask legally for the damage caused, metal stress and trouble.