A Burkina Faso prosecutor launched an investigation after 12 people died the same night in detention cells, hours after they were arrested for suspected terrorism-related offences.
The case comes weeks after advocacy group Human Rights Watch said it believed Burkina Faso security forces summarily executed 31 unarmed detainees during operations against Islamist militants.
The prosecutor, Judicael Kadeba, said in a statement the incident took place Fada N’Gourma, east of the capital Ouagadougou.
He said 25 people were arrested during the night of May 11 – 12 by Burkina Faso security and defence forces for suspected terrorism in a village in the Fada N’Gourma area.
“Twelve died during the same night in cells where they were held,” Kadeba said.
Burkina Faso has been battling armed Islamist insurgents, some with ties to al Qaeda and Islamic State, since 2017.
Militants strengthened their foothold in the north-east and eastern parts of the country around the tri-border region with Niger and Mali, the Liptako-Gourma region.
HWR said in April militants killed more than 300 civilians in Burkina Faso, while government killed several hundred men for alleged support of the groups.
Burkinabe officials promised to investigate similar allegations in the past, but rights group say government has not done enough to hold perpetrators accountable.