At least 85 people, including women and children, have been killed after a "mistaken" army drone attack on a religious gathering in northwest Nigeria, according to authorities.

The national emergency management agency also said at least 66 people were injured in the strike.

It is the latest in a series of attacks that have killed civilians.

Nigerian President Bola Tinubu called Sunday night's incident in Kaduna state "a bombing mishap" which was "very unfortunate, disturbing, and painful", as he ordered an investigation.

Military airstrikes have reportedly killed around 400 civilians since 2017 as the army aims to quash armed groups.

In the latest attack, scores of people were killed in the village of Tudun Biri as they marked a Muslim holiday.

The victims were killed by drones "targeting terrorists and bandits", according to officials.

Nigerian army chief Lieutenant General Taoreed Lagbaja visited the village and apologised for the airstrike.

"Terrorists often deliberately embed themselves within civilian population centres," Major General Edward Buba, spokesman for Nigeria's defence headquarters, said about Sunday's incident.

Troops who were carrying out aerial patrols saw a group of people and "wrongly analysed and misinterpreted their pattern of activities to be similar to that of the bandits" before the drone strike, said an army spokesman.

Witnesses reported two explosions, within 30 minutes of each other.

Villagers first heard a loud blast after 9pm local time (8pm UK time), forcing them to run to safety.

When the villagers realised it was a bomb, they started helping the injured and moving those who had died. Then, another blast was heard, killing more people, the witnesses said.

One civilian, Musa Shehu, said he had lost two wives, while his youngest daughter was injured and taken to hospital.

Another witness said those caught up in the attack, who came from four villages, were searching for answers.

The person said some of the infants who survived were "taken away from their dead nursing mothers" in what was a "terrible experience".

In January this year, an airstrike reportedly killed dozens of cattle herders in the central state of Nasarawa.

Human Rights Watch said the Nigerian air force "provided little information and no justice" over that incident.

Dozens of civilians also reportedly died in a strike on Zamfara state the month before.