Singer-composer Shankar Mahadevan says he is honoured to create the signature tune for the Directorate of Revenue Intelligence (DRI)."An honour to have created the signature tune for our Directorate of Revenue Intelligence (DRI)! Thank you for the love and affection," Mahadevan tweeted on Tuesday. The DRI is India's chief anti-smuggling intelligence, investigations and operations agency.The Directorate is run by officers from the Central Board of Excise and Customs who are posted in its various Zonal Units as well as in Indian embassies abroad as part of the Customs Overseas Intelligence Network. Mahadevan is known for composing music for films like "Zindagi Na Milegi Dobara", "Don", "Kabhi Alvida Naa Kehna", "My Name Is Khan", "Wake Up Sid", "Dostana" and "2 States".