The group, in a statement on its website, claimed responsibility for the incident which occurred last Saturday night.
The attack on the terminal has led to an acute shortage of crude oil both for export and for local processing.
The Forcados terminal accounts for over 400,000 barrels of crude oil exported daily and is ranked among the biggest terminals in the country.
The attack came a few days after President Muhammadu Buhari issued an order that more troops should be deployed to the Niger Delta region to protect oil installations.
In the statement, NDA said it enjoys support from Northern, Western and Eastern parts of the country.
The group, in the statement titled: “Operation Red Economy,” said its move was to protest the federal Government’s inability to tackle critical national issues including the anti-corruption war.
An official of the Nigerian National Petroleum Corporation (NNPC), who spoke under the condition of anonymity, disclosed that a high-powered delegation has been dispatched from Abuja to carry out an on-the-spot assessment on the affected installations.
Lt. Col. Isa Ado, the spokesman of the Joint Task Force codenamed Operation Pulo Shield, did not pick calls on his phone for confirmation of the incident. A senior military officer however confirmed the attack.
The Media Relations Manager of Shell, Mr. Precious Okolobo, in an email response to enquiries, said: “SPDC is investigating the source of a crude oil spill which was observed on water around Forcados Terminal on Sunday (February 14). This initial investigation will enable the company to quickly determine what suitable response is further needed.”
The group also demanded the immediate release of the detained leader of the Indigenous Peoples of Biafra (IPOB), Mr. Nnamdi Kanu, as directed by the courts.
It said: “We are a group of young Niger Deltans who have support from other parts of Nigeria, namely Northern, Western and Eastern parts.
“We have watched with keen interest, the way and manner in which the President Muhammadu Buhari-led APC government runs the affairs of this country, and we are not pleased with the way things are going.
“For instance, the so-called anti-corruption fight is directed at perceived enemies of the government, and those who are sympathetic to former President Goodluck Jonathan. We wonder why these persecutions, despite the peaceful manner Jonathan handed power over to the All Progressives Congress.”
“So far, the only two governorship elections that were conducted under this government were and still remain the most controversial elections in the history of this nation,” it said.
The group further demanded that: “The ownership of oil blocks must reflect 60 percent for the oil-producing people and 40% for the non-oil producing people. The only Nigerian Maritime University sited in the most appropriate and befitting place in Okerenkoko must start the 2015/2016 academic session, immediately.
“The Minister of Transportation, Mr. Rotimi Amaechi, should apologise to the Ijaws and the entire Niger Delta people for his careless and reckless statements about the siting of the University.
“The Ogoniland and indeed, all oil polluted lands in the Niger Delta must be cleaned up and compensation be paid to all oil-producing communities”.