Kolkata /Mumbai /Bangalore /Chennai, Dec 25 (ANI): Christians across various cities in India reveled in festive spirit as they sang carols in decked up churches while attending special midnight mass prayers on the Christmas Eve. In Kolkata, devotees gathered to attend the special mass and sang carols to celebrate the Christmas spirit. A large number of people gathered at the San Thome Church in Chennai and participated in the Christmas celebrations with fervour.