Human Rights Watch says Mali's former military rulers are behind the disappearance of at least 20 soldiers allegedly linked to an attempted counter-coup.

A report by the New York-based group charges Captain Amadou Sanogo and his forces rounded up 80 security personnel, including the 20 missing soldiers.

Captain Sanogo and his soldiers led a coup in March and blamed the 80 for a counter-coup attempt in late April. Under intense international pressure, Captain Sanogo yielded power to an interim government. But the international community says he continues to meddle in government affairs.

Human Rights Watch researcher Corrina Dufka says pro-Sanogo troops tortured their suspected rivals at two bases.

“In response to the counter-coup attempt, troops loyal to Amadou Sanogo and the CNRDR rounded up those that they people they believed were involved in the coup brought them to at least two bases, subjected them to some horrific forms of torture and then, according to witnesses within Kati camp, took out 20 of them, executed them and likely deposited their bodies in a mass grave.”

The Human Rights Watch report cites witnesses who say the torture included severe beatings, suffocation, sexual assaults, denial of food and water and burning with cigarettes.