Lagos:  Four Nigerian police officers and two civilians were killed during a gunfight with suspected separatist militants while they were on patrol in the southeast of the country, according to police.

The Indigenous People of Biafra, or IPOB, separatist group, and its armed wing, the Eastern Security Network, are active in Imo State, where the attack happened on Friday morning.

In the last two years, attacks blamed on IPOB have claimed the lives of dozens of police officers in Nigeria's southeastern states, where the group campaigns for a separate state for the Igbo ethnic group.

Also Read: UN Women calls for action against sexual violence amid conflict in Sudan

Imo state police released a statement that read, "Four police officers attached to Area Command Ngor-Okpala paid the ultimate price having engaged unsuspecting IPOB and ESN militia dressed in black and red regalia in a shoot out."

Two civilians were killed by a stray bullet fired by the criminals. Despite repeated denials, IPOB has not been responsible for attacks on police, local government, or electoral agency buildings.

Also Read: After the urine incident, now a drunken passenger in the flight did such an act, created a ruckus

Nigeria is a sensitive country when it comes to secession, as a three-year civil war that claimed more than 1 million lives began when Igbo army officers in the southeast declared an independent Biafra Republic in 1967.

The most populous country in Africa is split almost evenly between a predominantly Christian south and a predominantly Muslim north, with numerous ethnic groups present throughout.

The military is battling a 14-year-old jihadist insurgency in the northeast and heavily armed bandit militias in the northwest and central states, in addition to separatist violence, which is just one security challenge President-elect Bola Ahmed Tinubu must deal with.

Also Read: In their bilateral trade, Bangladesh and India are phasing out the use of the US dollar

The election that Tinubu, a former governor of Lagos, won in February was marred by technical issues, delays, and allegations of widespread vote rigging from the opposition. He will take office next month.