Attacks on Nigeria's energy facilities by groups calling for the Delta region to receive a greater share of the OPEC member's oil wealth have cut crude production, which stood at 2.1 million barrels per day at the start of the year, by a third.
The Niger Delta Greenland Justice Mandate said it bombed the Unenurhie-Evwreni delivery line in Ughelli, Delta state, at around 01:00 a.m. (0000 GMT) on Thursday. The line is operated by NPDC, a subsidiary of NNPC.
A military source said dynamite was used to blow up the pipeline. An NNPC spokesman could not immediately be reached for comment.
It comes days after Niger Delta Avengers, which has claimed responsibility for most of the attacks on energy facilities in the region since the start of the year, said it carried out its first attack since declaring a break in hostilities in August to pursue talks with the government.
The Avengers said on Saturday there had been no progress in meeting their demands.
The Greenland Justice Mandate, which has never agreed to cease hostilities, said in a statement it had blown up the pipeline "to prove to the wicked and ungrateful multinational oil companies and their Nigerian military allies... that we own our lands".