Nigeria's military said on Wednesday that there has been no evidence of ​civilian casualties from an airstrike on militants ‌in the northwest Zamfara state this month, calling reports of large death tolls unverified and misleading.

Amnesty International said ​this week that at least 100 civilians were ​killed in the May 10 airstrike on ⁠a crowded market in Tumfa village, urging authorities ​to open an immediate investigation.

Citing witnesses, Amnesty said ​that many of those killed were women and children. Local media also reported a similar death toll.

"No credible, substantiated ​evidence of civilian casualties has been established through ​any official assessment or independent verification," Defence Headquarters spokesperson Major-General ‌Michael ⁠Onoja said in a statement.

He said the strike was conducted under international humanitarian law and targeted a "confirmed high-level gathering" of militant leaders in the ​village, which ​was based ⁠on multi-sourced intelligence.

Onoja added that the nature of the strike meant that immediate ​casualty verification was difficult, but a ​post-strike ⁠assessment showed that "several terrorists were neutralised."

Nigeria's military has been battling bandits in the northwest but often describes ⁠them ​as terrorists. It is also ​battling a 17-year Islamist insurgency in the northeast.