At least 23 people were killed when fire broke out at a prison housing political prisoners in the Ethiopian capital, the government said Monday.

The blaze erupted Saturday at Addis Ababa's high security Qilinto prison.

An earlier government statement said just one person had died and six were injured in the fire, but the official toll was updated later in the day to 23 people dead, a figure more closely reflecting local media reports.

The government statement said 21 of the inmates died from suffocation and a stampede while the two others were killed while trying to escape the prison, according to the state-controlled Fana Broadcasting Corporation.

Local news and social media on Saturday reported gunfire heard from the prison as it burned. Amateur videos posted online showed a thick plume of dark smoke rising from the site on the outskirts of the city.

Two buildings were damaged in the fire while nine injured prisoners and police are being treated for injuries, Fana reported. The remaining inmates have reportedly been moved to other facilities.

There has been no word on the cause of the fire.

Qilinto houses many of those arrested in an ongoing government crackdown against months of protests in the central Oromo region and elsewhere.

Human Rights Watch estimates that more than 400 people involved in the anti-government protests have been killed by security forces since November.