The Roman Catholic Church has accused the Sri Lankan army of shooting unarmed protesters and desecrating a church during demonstrations against water contamination.
In an unusually strongly worded statement on Wednesday, the Archbishop of Colombo condemned "unhesitatingly" the military shooting that killed three people and wounded more than 50 others in a village just outside the capital last Thursday.
Cardinal Malcolm Ranjith accused Sri Lanka's army of violating the sanctity of St Anthony's church, beating up people who rushed there to escape the army shooting.
"We wish to condemn unhesitatingly the attack that was carried out by some elements of the [armed] forces on people who had sought refuge at St Anthony's church," the archbishop said.
"Such actions cannot be accepted by anyone... We do not accept using one's power in a repressive manner to suppress protests, even if they get out of hand."
The military opened fire on Thursday on thousands of unarmed residents who were protesting against the contamination of their ground water supply, allegedly by chemical waste from a rubber glove factory.
Government ministers said the military was acting in self-defence because protesters threw petrol bombs and shot at them at the instigation of a third party bent on discrediting the government.
Local media reports said soldiers barged into the church, ordered some of the people, including children, to kneel down and then beat them with sticks. Troops were also accused of opening fire inside the church compound.
Journalists said the military attacked them and damaged cameras before turning on the protesters.
Christian priests and nuns joined hundreds of faithful in staging a candle-light vigil in the capital on Wednesday to protest against the military action.
The vigil and the cardinal's statement came as two of the victims were buried in the village of Weliweriya on Wednesday amid mounting protests from opposition political parties against the military attack.
The main opposition United National Party (UNP) has criticised the army's plans for an internal military probe and demanded an international investigation into the deadly crackdown.
"We cannot accept the government getting one of its henchmen to probe the killings," UNP general secretary Tissa Attanayake told reporters in Colombo on Monday.
Rights group Amnesty International also said the army should not be allowed to investigate itself.
"The Sri Lankan army should have never been policing unarmed demonstrators in the first place," Polly Truscott, Amnesty International's deputy Asia-Pacific director, said in a statement.
"Having them investigate their own alleged abuses is simply ridiculous," she added.
Several people are still being treated in hospitals after the military attack, medical officials said.