Prime Minister Narendra Modi has flagged off a marathon in New Delhi, called the 'Run for Unity', on the birth anniversary of Sardar Vallabhbhai Patel. Home Minister Rajnath Singh, who attended the early morning event in Major Dhyan Chand National Stadium, addressed the people who have gathered there. In his address, he asked citizens to work for India's unity. PM Modi also said unity in diversity was India's greatest asset and people must work toward building the nation based on this source of strength.