According to Mali's army, soldiers conducted a successful operation against jihadists in Moura, in the centre of the Sahel nation, killing hundreds.

But another version of events holds that the army committed a civilian massacre.

- What happened in Moura? -

On Friday, Mali's army stated that it had killed 203 militants in the Moura area, during an operation that lasted between March 23-31.

However, many viewed the announcement with scepticism as it followed widely shared social media reports of a civilian massacre in Moura.

In a report on Tuesday, Human Rights Watch (HRW) estimated that Malian forces and foreign fighters killed about 300 civilians during the operation.

The United States, European Union, United Nations and Mali's former colonial power France have all raised concerns about the possible killing of civilians in Moura.

- What does Mali's army say? -

In its April 1 statement, Mali's army described its operation in Moura as "large-scale".

Mali's army also said that it had captured 51 militants in Moura and that it carried out a "systemic cleansing of the entire area".

In another statement on Tuesday night, the army said that it had identified "terrorists" hiding among the local population after taking control of the town.

Moura is situated in central Mali -- a hotbed of violence where al-Qaeda-affiliated jihadists are active.

Central Mali is one of the flashpoints of an Islamist conflict that first emerged in northern Mali in 2012, before spreading to central Mali and neighbouring Burkina Faso and Niger.

- What do the witnesses say? -

Witness who spoke to HRW said that Malian forces and white foreign soldiers arrived in Moura on March 27.

Over the ensuing days, Malian and foreign fighters allegedly rounded people up and executed them in small groups, according to their accounts.

HRW estimated that about 300 civilians were killed in total, with the vast majority of the victims being ethnic Fulanis.

One eyewitness told the rights group: "I lived in terror, each minute, each second thinking it would be my turn to be taken away and executed."

Other witnesses said that detainees in Moura were forced to dig mass graves before being executed.

- Who conducted the operation? -

Malian forces were operating in tandem with white foreign soldiers, according to HRW, who are believed to be Russian because witness accounts refer to them as non-French-speaking.

Russia has supplied what are officially described as military instructors to Mali. However, the United States, France, and others, say the instructors are operatives from the Russian private-security firm Wagner.

Mali's army did not mention foreign fighters in its statements on Moura.

However, it said that the operation involved five helicopters of Soviet or Russian design -- without specifying who piloted the aircraft.

Malian authorities have repeatedly denied hiring Wagner operatives. They also routinely defend the rights record of the Malian army.

- Can the truth emerge? -

The UN peacekeeping mission in Mali, known as Minusma, has said that it was consulting with Malian authorities in order to establish what happened in Moura.

HRW has demanded an impartial investigation, and suggested that Mali ask the African Union and the United Nations for assistance.

Former colonial power France, the United States and also the Malian human rights commission, an NGO, have also demanded investigations.

Mali's under-equipped army has also often been accused of committing abuses during the conflict.

In response to fresh reports of abuses, Mali's army said on Tuesday that "unfounded allegations" aimed to tarnish its image. It added that respect for human rights remained an operational "priority".

AFP was unable to verify the Malian army's version of events, nor the reports of civilian deaths.

Poor access to Mali's conflict areas and a relative lack of independent information sources means that figures provided by either the government or armed groups are difficult to confirm.