[LAGOS] Militants have blown an offshore oil facility operated by US oil group Chevron in southern Nigeria, the navy and the company said on Friday, in renewed violence that could hit exports in Africa's largest oil producer.
"There was an attack on a Chevron facility near Escravos on Wednesday night. The incident happened about four nautical miles from Escravos, near Warri, in Delta state," spokesman Chris Ezekobe told AFP.
Mr Ezekobe said "militants using explosives blew up the Okan platform, a collection facility for offshore oil and gas that feeds the Escravos terminal".
He said it was not known how many people were on the platform at the time, but that there were no known casualties.
The navy was working with other security agents to track down the culprits, he added.
"A previously unknown group called the Niger Delta Avengers has claimed responsibility for the incident," the spokesman said, confirming a statement on the group's website.
"But we are not ruling out the involvement of former Niger delta militant leaders, particularly Tompolo, who is wanted on fraud charges."
Chevron Nigeria Limited (CNL), which operates the joint venture with Nigeria's state-run oil firm, confirmed in a statement that the facility was attacked at 11:15 pm (2215 GMT) on Wednesday.
The company blamed "unknown persons" for the breach, adding: "The facility is currently shut-in and we are assessing the situation, and have deployed resources to respond to a resulting spill.
"The incident has been reported to the relevant security and regulatory bodies.
"CNL continues to monitor the situation and remains committed to meeting its business and corporate obligations, including protecting people and the environment and conducting its operations reliably and safely."
There was no immediate indication of the volume of crude affected but a Chevron official, who asked not to be identified, said the attack would hit gas supply to power plants already affected by almost daily outages.
Attacks on oil and gas facilities have increased since January when Mr Tompolo - whose real name is Government Ekpemupolo - was declared wanted on multi-million-dollar corruption charges.
The former leader of militants who wreaked havoc in the creeks and rivers of the delta in the 2000s is accused of defrauding the government of more than US$175 million.
The offences linked to government maritime security contracts are alleged to have taken place between 2012 and last year, a court in Lagos has been told.
The upsurge in attacks is another security headache for President Muhammadu Buhari, who is battling Boko Haram Islamists in the northeast and an increase in violence between nomadic herdsman and farmers in central and southeast Nigeria.
It also risks hitting crude supplies at a time when Nigeria's oil-dependent economy is facing a slump because of the fall in global prices.
Mr Tompolo, an ally of former president Goodluck Jonathan, was a prominent leader of the Movement for the Emancipation of the Niger Delta (MEND), which demanded a fairer share of oil revenue for local people, most of whom still live in poverty.
The Niger Delta Avengers group is thought to involve Mr Tompolo's supporters unhappy about the charges against him and the winding down of a government amnesty programme that ended the unrest in 2009.
But Mr Tompolo has previously said he is not part of the group.