Opposition MPs in Parliament are wearing black shawls in Parliament in protest of the swearing-in of Premalal Jayasekera.
Jayasekera, who was convicted of murder, took oaths before Speaker Mahinda Yapa Abeywardena as a Member of Parliament.
He was escorted to Parliament to attend today's Parliamentary session, this morning.
Jayasekera's presence in Parliament has sparked a major controversy in the political sphere.
The Court of Appeal yesterday issued an interim order informing the Prisons Deparment to allow Jayasekera to attend Parliamentary sittings.
Jayasekera filed a writ application with the Court of Appeal last week, seeking permission to attend parliamentary sittings.
Jayasekera was convicted for a murder in the Kahawatte area and given death sentence just days before the last Parliamentary election.