The suspects arrested included the family members of the St. Sebastian's church's attacker, he revealed.

Father Jude Fernando, head of St. Antonio Church, called on "all communities to be peaceful, pray for us and be calm."

"I humbly request and I ask, please pray, don't make any blunders, be calm, be quiet and keep and continue this fraternity and show our love and concern for one another."

The multiple suicide attacks on Sunday have claimed more than 300 lives and over 500 people were also injured in the island country. The Sri Lankan government has imposed curfew at night and declared a state of emergency to give the military and police more powers to contain the situation and prevent further possible bomb attacks.