Nikhil Gupta, a 52-year-old Indian national, has been extradited from the Czech Republic to the United States, where he is currently being held at the Metropolitan Detention Center in Brooklyn, according to the federal Bureau of Prisons website and a source familiar with the matter. Gupta is suspected by US authorities of being involved in a failed plot to assassinate Gurpatwant Singh Pannun, a US resident and advocate for a sovereign Sikh state in northern India.