Nigeria's army has offered 290 million naira (€1.3m) for information leading to the capture of 19 leading members of Islamist sect Boko Haram.
Boko Haram's insurgency has killed hundreds this year.
The insurgency wants to impose strict sharia, or Islamic law, in the country of 160 million.
The country is split roughly equally between Christians and Muslims.
The military Joint Task Force (JTF) in northeast Borno state offered a reward of 50m naira for the sect's self-proclaimed leader Abubakar Shekau.
It offered 25m naira for each of the men said by the JTF to be his main commanders: Habibu Yusuk, Khalis Albarnawai, Momodu Bama and Mohammed Zangina, and 10m naira for 14 other senior members.
Boko Haram's core group, believed to be led by Mr Shekau, still focuses its attacks in its northeast base but the group is split into different factions spread across the north of Africa's most populous nation.
It has carried out several attacks in the capital Abuja, including a suicide car bombing on the United Nations headquarters last year that killed at least 24 people.
Britain last week banned a Nigerian Islamist group known as Ansaru it said was aligned with al-Qaeda.
Boko Haram has largely had a domestic agenda but Western governments are increasing worried about Islamists in northern Nigeria linking up with outside jihadist groups such as al-Qaeda's north African wing.