KOCHI: The National Investigation Agency (NIA) on Tuesday arrested Siddique ul Aslim, a founder member of 'Ansar-ul-Khilafah, the Kerala unit of the ISIS terrorist. Siddique is a native of Kanyakulangara in Thiruvananthapuram. He was deported from Saudi Arabia. He was arrested from New Delhi and was produced before a special NIA court in Ernakulam. The investigation team has taken him into custody till Friday for further questioning.