Washington: Prime Minister Narendra Modi, who is in the US on the fourth leg of his five-nation tour, met the heads of US think tanks here. "Probing the minds of those who shape foreign policy. PM @narendramodi at an interaction with think tanks in Washington," Ministry of External Affairs Spokesperson Vikas Swarup tweeted on Tuesday along with a picture of the meeting. Earlier, Modi attended an event in which Indian idols lying in the US have been returned to India. The PMO tweeted: "After history & culture, it's current & strategic affairs. Think tanks meet PM, share perspective on various issues."