BAMAKO (Reuters) - A French military strike on armed militants in northern Mali last month inadvertently killed Malian soldiers who were being held hostage by the Islamist group, the West African nation’s Defence Ministry said on Monday.

The French army has previously said that 15 members of the Islamist militant group Ansar Dine were taken “out of action” in the Oct. 23 operation in the Abeibara region, which involved Mirage jets, attack helicopters and ground forces.

In the week following the raid however, Malian media reported that 11 soldiers had also been killed. French and Malian military and government officials initially declined to comment on the deaths.

In a statement dated Oct. 31 but only distributed on Monday, the Defence Ministry said that “Malian soldiers, detained by the terrorists, died” in the attack without giving a death toll.

It was not immediately clear why the distribution of the statement, which was drafted following a meeting between the defense minister, France’s ambassador to Mali and a French military official, appeared to have been delayed.

Paris has maintained that military intelligence had identified the site as a militant camp and French army spokesman Colonel Patrik Steiger declined to comment on the Malian statement.

“Work is under way with the Malian authorities to determine the identities of individuals killed. It’s up to Mali, a sovereign country, to communicate on this subject, not the French forces,” he said.

France intervened in 2013 against Islamist militants that seized northern Mali a year earlier. Around 4,000 of its troops remain in West Africa’s Sahel region as part of Operation Barkhane, a cross-border anti-terrorism operation.