FACTBOX - Nigerian oil rebels reinstate delta ceasefire

REUTERS - Nigeria's main militant group reinstated a ceasefire on Sunday in the oil-producing Niger Delta to allow for peace talks with the government.

The Movement for the Emancipation of the Niger Delta (MEND), whose attacks have battered Africa's biggest energy industry in the last three years, said the government expressed a readiness last week to engage in serious talks to address their concerns.

Here are some details on the three former MEND leaders.

ATEKE TOM

A former gang leader in Rivers State in the eastern Niger Delta for around a decade, Ateke Tom set up the Niger Delta Vigilante (NDV), one of several groups to enjoy strong backing from politicians who used them to help rig elections.

The NDV was involved in some of the heaviest clashes in years in the oil hub of Port Harcourt in July and August 2007, when more than 100 people died in fighting with a rival gang involving automatic weapons and rocket-propelled grenades.

Tom had largely operated independently of the Movement for the Emancipation of the Niger Delta (MEND), the umbrella militant group in the region, but his faction claimed at least two attacks against the oil industry last year.

Security sources say he was heavily involved in oil bunkering, a lucrative trade in industrial quantities of stolen crude smuggled onto the international market.