Maligaon, November 2 (MExN):Northeast Frontier Railway Construction Organisation, Maligaon observed Rastriya Ekta Diwas (National Unity Day) on November 2. The National Unity Day is celebrated to commemorate the 143rd birth anniversary of late Sardar Vallabhbhai Patel. NK Prasad, General manager, NF railway, Construction Organisation, in a release also stated that he administered a unity pledge to employees and officer in the Construction Head Quarter premises. He appealed to all to respond the call of Sardar Patel in this regard.