Nigeria's police force has taken to Twitter to express anger and demand answers from the army after soldiers killed three police officers in a gunfight on Tuesday.
A civilian was also killed when a police team transporting a suspect in the north-eastern state of Taraba came under attack from the military.
The troops fired at the undercover officers because they mistook them for kidnappers, according to the military.
But the police seem displeased with the army's account of the incident, taking to their Twitter account to question their actions.
Photos and names of the officers killed were posted with the hashtag #WhereIsEspiritDCorp: sergeants Usman Danzumi and Dahiru Musa and inspector Mark Ediale.
Nigerians have been shocked to see the row played out in a public forum.
The police also want to know the whereabouts of the handcuffed suspect, Alhaji Hamisu, who is alleged to be a notorious kidnap kingpin.
He escaped in the gun battle and the police accuse the soldiers of releasing him.
This incident highlights the fractious relationship between Nigeria's security agencies as they fight Islamist insurgents in the north-east, confront deadly clashes between farmers and herdsmen and rampant kidnappings nationwide.
President Muhammadu Buhari, a former military general, called a security meeting after the police tweets appeared.
But Chief of Air Staff, Marshal Abubakar, who briefed the media after the meeting, did not comment on the issue.