At least seven people died after clashes broke out between security forces and worshippers taking part in a religious ceremony marking Epiphany in northern Ethiopia over the weekend, officials said.

Authorities in the Horn of Africa country’s Amhara region said they were yet to determine the causes of the violence that first erupted on Saturday in the town of Woldiya, more than 500 kilometres north of the capital Addis Ababa.

“Attempts to unblock roads and prevent the destruction of property are still ongoing. The situation has improved (since Sunday) but we are still having to undertake such measures,” said Amare Goshu, a police commissioner of the district.

Attempts to unblock roads and prevent the destruction of property are still ongoing. The situation has improved (since Sunday) but we are still having to undertake such measures.

One member of security forces deployed to quell the violence was among the dead, he said. Orthodox Christians use Epiphany celebrations to mark the baptism of Jesus Christ.

It was not immediately clear if the violence is related to unrest that plagued the country in 2015 and 2016.

The United Nations Human Rights Agency released a statement saying it was ‘concerned about the use of force by security officials against worshippers’.

#Ethiopia: We’re very concerned by the use of force by security officials against worshippers celebrating the Ethiopian Orthodox festival of Epiphany that left at least 7 people dead. We urge for an investigation to ensure accountability for any violations https://t.co/zKLG0qqKxP — UN Human Rights (@UNHumanRights) January 23, 2018

In Ethiopia’s central Oromiya province, hundreds were killed over that period in violence triggered by allegations of land grabs, with protests then broadening into demonstrations over political restrictions and perceived rights abuses.

Protests had also previously taken place in the Amhara region, with dozens dying in violence sparked by a territorial dispute.

Ethiopia is a Western ally against Islamist militants in neighboring Somalia and an economic power seen as a centre of relative stability in a fragile region.

The government in Addis Ababa has sought to calm political turmoil by announcing reforms and releasing dissidents. Last week, a senior opposition leader jailed for collusion with anti-government rebel groups was freed alongside 114 other inmates.