Prime Minister Dr Manmohan Singh, Union and state ministers and a host of leaders of various political parties today greeted Tamil Nadu Chief Minister Mr M. Karunanidhi who turned 87. Dr Manmohan Singh telephonically greeted the octogenarian leader. Mr Karunanidhi placed wreaths at the memorials of his mentors late chief minister and founder of DMK Annadurai and Periyar.<br/>Earlier, the chief minister planted a sapling at his residence and celebrated his birthday with his family members. Thousands of party workers greeted the leader at the DMK headquaters.<br/><br/>