Hundreds of Catholics prayed outside the bombed St Anthony's Church in Colombo on Tuesday, marking one month since the Easter Sunday suicide attacks that killed 258 people in Sri Lanka.
The faithful lit candles and offered prayers even as the church, first built in 1740, was being restored following the devastating April 21 bombing.
Two other churches outside the capital and three luxury hotels in Colombo were also hit in the coordinated attacks blamed on local people and claimed by the ISIS.
Troops and police maintained tight security across the country on the anniversary, which also coincided with the partial reopening of Catholic schools after an extended Easter holiday.
At St. Joseph's College in Colombo, upper school students were seen returning to classes.
Public schools had reopened earlier in the month. Catholic schools reopened after army chief Mahesh Senanayake said security forces would ensure that students were not targeted by ISIS responsible for the Easter bombings.
A Catholic spokesman in Colombo said primary classes will resume next week.
President Maithripala Sirisena has vowed to crush ISIS blamed for the Easter bombings that also left 500 injured.
Christians make up 7.6 percent and Muslims 10 percent of mainly Buddhist Sri Lanka, which has been under a state of emergency since the attacks.