Sixteen Nigerian soldiers have been killed on a mission to halt clashes between two communities in the southern state of Delta, an army spokesman said on Saturday.
The troops deployed in the Bomadi region "were surrounded by some community youths and killed on Thursday, 14 March," Brigadier General Tukur Gusau said in a statement.
"The reinforcement team... was also attacked leading to the death of the Commanding officer, two majors, one captain and 12 soldiers," said Gusau, acting director of defence information.
The soldiers had "responded to a distress call" following trouble between the Okuama and Okoloba communities.
"The Chief of Defence Staff, General Christopher Gwabin Musa, has directed the immediate investigation and arrest of those involved in the heinous crime," the statement said.
"So far, a few arrests have been made while steps (are) in place to unravel the motive behind the attack."
According to local media reports, the two communities have clashed repeatedly over land ownership in recent weeks leaving several people dead.