MEND, operating from Nigeria's south, says it will attack Muslims to protect Christians in Nigeria.
Starting May 31, Nigeria's oil militant group, Movement for the Emancipation of the Niger Delta said it will target mosques and Islamic institutions, in a new terror campaign, "in defence of Christianity."
Operating from oil rich Niger Delta creeks, MEND is Nigeria's foremost collection of terror gangs united by a struggle to control the region's oil wealth, and criminality.
The group issued its newest threat just a week after it claimed responsibility for the killing of 12 police officers in the southern Bayelsa state.
"The bombings of mosques, haj camps, Islamic institutions, large congregations in Islamic events and assassinations of clerics that propagate doctrines of hate will form the core mission of this crusade," MEND spokesman Jomo Gbomo said in an e-mailed statement on Sunday.
The campaign is codenamed "Operation Barbarossa," Mr Gbomo, thought to be pseudonym, said.
MEND says Barbarossa will not in any way interfere with the ongoing "Hurricane Exodus" - which killed the police officers and "on Saturday, April 13, 2013, at about 01:00 Hrs, swept through the Ewellesuo community, Nembe, Bayelsa State, leaving the destruction of Well 62, belonging to Shell Petroleum in its wake."
Precious Okolobo, a Lagos-based spokesman for Shell's Nigerian unit, told Bloomberg he couldn't confirm the Saturday attack Well 62.
MEND announced early this month it resumed attacks in Nigeria after Henry Okah, its leader, was sentenced last month to 24 years in prison in South Africa. Mr. Okah was found guilty of 13 counts of terrorism, including a bombing claimed by MEND in which 12 people died in Abuja on Oct. 1, 2010.
MEND agrees with Boko Haram's attacks targeted at Nigerian security agents - "including the prisons, for their role in extrajudicial killings, torture, deceit and corruption" - but said Boko Haram's attacks on Christians are not acceptable.
MEND says it will consider abandoning the operation if the Christian Association of Nigeria (CAN), the Catholic Church and Henry Okah, "one of the few leaders in the Niger Delta region we respect for his integrity", intervenes.
"Also the assurance for a cessation of hostilities targeted at Christians in their places of worship, made privately or publicly by the real Boko Haram leadership will make us call off this crusade," Mr. Gbomo added.
While MEND operates as the major terror gang in Nigeria's south - especially oil rich Niger Delta areas, including Lagos - Boko Haram operates largely in NIgeria's north, targeting security agencies, Christians, opposition Islamic clerics, foreigners and other perceived enemies.
Both groups are Nigeria's largest terror gangs. While MEND - triggered by fight for economic justice - partially accepted amnesty in 2009, the government is currently persuading Boko Haram - a terror gang whose self-professed motive is the islamization of northern Nigeria, to do same.