Eritrean Catholic bishops have called for “fasting and prayers” in the ongoing row with the government.
In the last few weeks the government has closed health centres and clinics run by the church.
The bishops have been critical of what they say is a lack of justice and bad governance by President Isaias Afwerki’s government.
On Monday, government security agents arrested a nun and another worker for not handing over the keys for their health centre in Anseba region sources told the BBC.
The religious leaders say the recent events had “saddened our church and people”.
“Let’s especially remember in our prayers, the patients who were affected by the measure taken and those who could be affected,” they said.
In their “Peace for All” letter in April, they said “despite the peace [with Ethiopia] the people have not found peace and hope”.
They expressed, at the time, their concern at the alarming rate of young people leaving the country in the wake of the opening of the borders with Ethiopia.
Meanwhile, on Sunday in the city of Keren, followers of Faith Mission church were arrested in a raid by government security, reports say.