BAMAKO, Mali - A mass grave containing 21 skulls has been found near the Kati military barracks, formerly the fief of the country's military strongman, Mali's chief prosecutor announced Wednesday.

The remains are believed to be of soldiers who opposed the leader's rise to power, and their discovery paves the way for Gen. Amadou Haya Sanogo to be charged with murder, prosecutor Daniel Tessougue said.

A forensic team began the exhumation Tuesday at 6 p.m. and finished at 3 a.m. Wednesday. The spot where remains were found matches the place where witnesses said about 20 soldiers were shot and killed by troops loyal to Sanogo in May 2012.

"I went there myself, and we uncovered 21 skulls," said Tessougue, adding that it appeared the victims had died while chained together.

In a move that has been applauded by the international community, the prosecutor arrested Sanogo last week, charging him with complicity in the kidnapping of his fellow soldiers. Now that the bodies have been found, Tessougue says, Sanogo will also be charged with assassination.

On March 21, 2012, Sanogo led a military coup that reversed two decades of democracy in this landlocked nation. Sanogo, at that time a captain, was backed by the rank-and-file soldiers at the Kati barracks, who marched on the presidential palace, toppling the former leader.

Sanogo was opposed, however, by the elite paratroopers known as the Red Berets, who made up the guard of the country's ousted president. When the Red Berets tried to lead a countercoup April 30, 2012, Sanogo responded with blunt force, organizing what human-rights groups describe as a purge of the military.

This summer, Mali held its first presidential election since the coup, electing Ibrahim Boubacar Keita, known by his initials, IBK. Soon after the election, Sanogo was promoted to four-star general, and rights groups worried that the new president would continue the former government's policy of looking the other way when Sanogo meddled in state affairs.

But anthropologist Bruce Whitehouse, an expert on Mali, says that if you looked carefully, the new administration was taking subtle steps to defang the coup leader, capped by his arrest last week.