The Nigerian army has arrested two soldiers after a viral video allegedly showed them torturing a civilian.

In the footage, a man in military fatigues and another in civilian clothing repeatedly kick and whip a third shirtless man, as he repeatedly pleas for mercy.

"No, no sir, abeg! [I beg]. I will confess sir, abeg!" the man cries out.

The army has expressed "utmost dismay" at the "unprofessional conduct" allegedly displayed by the officers.

"It is instructive to mention that the soldiers involved in that unprofessional conduct have been clearly identified and arrested," the army added in a statement on Wednesday.

The alleged assault took place in Nigeria's Rivers state, but the date is unclear.

The circulation of the video on social media platforms earlier this week prompted widespread condemnation of the soldiers and Nigerian army, with one user on X describing the soldiers' behaviour as "highly cruel, barbaric and nothing but abuse of power".

The army has assured that it will conduct a thorough investigation to address the incident and promised to "sanction those involved".

International human rights groups have previously criticised Nigeria's army for alleged rights abuses, including torture, arbitrary arrests and extrajudicial killings.

Nigerian soldiers used to have a reputation for acting with impunity - for many years it was rare for soldiers to face disciplinary action if they attacked civilians.

But this has changed in recent years. Army chief Taoreed Lagbaja vowed to make the army more disciplined and professional when he was appointed last year.