Civilians are feared to have died after reports that Nigerian military jets struck a village market in the north-east of the country.
The attack took place near the border between Yobe and Borno states while an aircraft was said to be engaged in an operation against Islamist militants in the area, according to the Reuters news agency and local reports.
The Nigerian Air Force said it carried out "mop-up" air strikes on "identified terrorist locations" within the Jilli axis of Borno State on Saturday, but has not confirmed that it struck the market nor confirmed casualties.
The area is at the centre of the long-running Boko Haram insurgency, which has forced more than two million people to flee their homes and killed thousands.
The Nigerian Air Force's statement said follow-on strikes on Saturday were "aimed at fleeing remnants and regrouping cells seeking to exploit the difficult terrain".
