The Federal High Court in Abuja has ordered the remand of leader of the Indigenous People of Biafra (IPOB) Nnamdi Kanu till July 26.
The Department of State Services (DSS) took Mr Kanu to court on Tuesday same day his arrest was announced.
Kanu was re-arraigned on charges bordering on alleged treason.
Justice Binta Nyako said he is to be remanded in DSS custody pending the determination of his trial.
The IPOB leader appeared in court without his lawyer or any member of his defence team.
Kanu told the court that he decided to go underground because his house was raided but he was able to escape.
He said if he had not escaped, he might have been killed like other members of the group.
The judge, who advised him not to feel discomfiture to stand his trial, urged him to get across to his lawyer for the trial.
Kanu was first arrested on October 14, 2015, and arraigned on 11-count charges bordering on terrorism, treasonable felony, managing an unlawful society, publication of defamatory matter, illegal possession of firearms and improper importation of goods, among others