On Thursday a Nigerian crude oil pipeline was attacked by the rebel Movement for the Emancipation of the Niger Delta (MEND), thus the violence against Africa’s top oil producer was revived.

MEND claimed the attack over the Royal Dutch Shell's Forcados oil terminal, Reuters reports.

The attack showed the discontent of the militants towards the incapability of the government to handle the peace initiative, started in May when President Umaru Yar'Adua was inaugurated.

MEND said in a statement: “Our strategy is to nibble continuously on the oil industry until they are crippled. We are determined to make the military busy enough to justify the huge budget for security in the region.”

According to a Shell spokesman, the company closed some production and was cleaning up. Apparently dynamite was used to damage the pipeline and that a large volume of oil was spilled in the southern state of Delta.

The company refused to say the volume of the production that got affected. An industry source said that it could be between 20,000 and 50,000 barrels per day (bpd).

The attack occurred just as the company was restoring production after a wave of militant attacks and kidnappings took place in the Forcados area in February 2006 when 477,000 bpd were cut.

Before the explosion, output was at about 70,000 bpd, and by July it had been expected to rise with another 160,000 bpd.

Since the arrest of Henry Okah, a MEND factional leader, in September, a surge of violence has taken over the Niger Delta.

Okah's MEND has acknowledged four attacks on major oil facilities since October 21. However, it has denied the involvement in the attack that killed 21 Cameroonian soldiers at a border post on Monday.

MEND accused the Nigerian government for the attack, but the government denied any allegations saying that relations between the two countries were excellent, Reuters reports.