Police said that the parliament translator named Jamaldeen Noushad who allegedly has had links with IS terrorists would be kept under detention and questioned for three months.
On a tip-off to the DIG in charge of Kurunegala, the suspect was arrested by a special police team at Rajagiriya.
The suspect, Jamaldeen Noushad has served as a translator of parliament since 2006.
He has maintained close links with Zahran Hashim, who was considered the leader of National Thawheet Jamath.
The suspect is revealed to be an active member of the proscribed organization and conducted lectures on Islam extremism in Akurana and Kandy.
A senior investigator stated that the suspect was arrested on the information revealed by the Kurunegala hospital worker who was arrested on Thawheet Jamath links.
Police have also seized several suspicious equipment from the house of the suspect in Rajagiriya.
Details of the arrest have been reported to the parliament secretary general as well.