Khan, who is accompanying State Chief Minister Akhilesh Yadav for the presentation of a Harvard study on the Kumbh Mela pilgrimage, was detained for about 10 minutes for "further questioning" at Boston Logan International Airport Wednesday, according to Indian officials.

Once the visitors were cleared for entry by immigration, a woman officer of the US Customs and Border Protection wing of the Homeland Security took Khan to an adjacent room "for further questioning," sources said.