A week late on the first Sunday after Easter, no mass was held in any church across the country.
The involvement of a large number of women in the Easter Sunday attacks that killed more than 250 people and wounded almost 500 in the island nation prompted the government to take the extreme decision.
"Sri Lankans can make very good choices about how to approach that and the president's indication that these emergency powers would only be used to focus on the perpetrators of this bad crime I think is an important acknowledgement of that", she added. Sri Lankan authorities have arrested dozens of suspects and are searching for more militants with suspected links to ISIS.
Mr Wickremesinghe said investigators have been tracking the trail of explosives used to manufacture the bombs used to target churches and luxury hotels in the country.
Who are the NTJ?
The attack left 15 people dead, including six children.
Meanwhile, the government banned all kinds of face coverings that may hide people's identities.
Authorities banned National Towheed Jamaat over its ties to Mohammed Zahran, the alleged mastermind of the attacks that killed over 250 people a week ago.
According to a statement from the President's office, any face garment which "hinders identification" will be banned across the country.
Sri Lankan President Maithripala Sirisena on Monday named Deputy Inspector-General Chandana Wickramaratne as the acting police chief, even as incumbent police chief refused to step down over the Easter Sunday suicide attacks, an official involved in the process said.
"What happened last Sunday is a great tragedy, an insult to humanity", the cardinal said in a chapel at his residence, where the mass was attended by President Maithripala Sirisena and Prime Minister Ranil Wickremesinghe.
The firebrand cleric is said to have died in the attack on the Shangri-La, one of three Colombo hotels hit by suicide bombers at the same time as the churches. The niqab is a black veil made of thin fabric, often with a small opening from which a woman's eyes can peer out.
Sri Lanka on April 27 banned the NTJ and a splinter group linked to the ISIS. The head of Sri Lanka's Roman Catholics, Cardinal Malcolm Ranjith, expressed concern over the official probe into the attack, fearing that it might become a "flop".
However, Muslims in Sri Lanka - about 10% of the population - practice a more liberal interpretation of Islam.