The militant group came on the scene on in June 2016, with threats to unleash six missile attacks on Tuesday, June 7, 2016.
The security agency said Abari masterminded the spreading of an alleged coup plot against President Buhari.
The DSS also alleged that the arrested militant leader confessed to various crimes including threatening to bomb the Presidential Villa.
The JNDLF had earlier alleged that some military officers were planning to overthrow President Buhari.
The militant group came on the scene in June 2016, with threats to unleash six missile attacks on Tuesday, June 7, 2016.
The arrested JNDLF leader also reportedly confessed to writing threat letters to Nigeria Agip Oil Company (NAOC) and Shell Petroleum Development Company (SPDC) asking for N500 million and N250 million respectively from the oil giants.
The DSS also claims that he masterminded the bombing of an SPDC oil pipeline.
The security agency also arrested five persons in Kano State, suspected to be members of an ISIS sleeper cell.
The Niger Delta Avengers has also warned the Nigerian Navy to stop arresting innocent people and parading them as militants.