The Union Ministry of Home Affairs has handed over the probe into the alleged ricin poison terror plot to the National Investigation Agency (NIA), said a senior Gujarat ATS official on Saturday. The Gujarat Anti-Terrorist Squad (ATS) had arrested Dr Ahmed Mohiyuddin Saiyed, Azad Suleman Sheikh, and Mohammad Suhail Mohammad Saleem on November 9 last year for their alleged role in a plan to carry out a major terrorist attack with weapons and chemicals. The agency had booked the three under the stringent UAPA, or Unlawful Activities (Prevention) Act, besides invoking the Bharatiya Nyaya Sanhita and the Arms Act. The MHA has ordered to hand over the UAPA case concerning the ricin chemical plot to the NIA, Superintendent of Police (ATS) K Siddharth told PTI. Ricin is a highly poisonous substance that can be made from the waste material left over from processing castor beans. Gujarat ATS, which was probing the case, arrested Dr Saiyed, originally from Hyderabad, near Adalaj in Gandhinag