Onyema was reportedly apprehended Sunday night at a location in Isiala Ngwa North Local Government of the state.
The sergeant shot and killed one Ifeanyi Chidi Kalu and Izunna David Enyinnaya.
Commissioner of Police Janet Agbede said Onyema was tracked to Ijebu Ode, Ogun State, by detectives last week, but before he could be arrested, he left the place.
In a statement on Monday, police spokesman Geoffrey Ogbonna said, Sergeant Onyema would soon appear in court.
CP Agbede has visited the families of the slain men to commiserate with them for their loss.
THE EASTERN UPDATES