Lagos - The government has released a man who was arrested for tweeting pictures of an attempted jail break at the headquarters of the intelligence agency in Abuja, his younger brother told AFP Saturday.
Yusuf Siyaka Onimisi, who works for a national electricity firm, was arrested and held incommunicado for at least 11 days after tweeting the pictures.
"I confirm that my brother has been released. I spoke with him earlier today and our mum is with him in Abuja," Sanusi Onimisi told AFP on telephone from Kano.
"I thank all Nigerians, the media and human rights organisations within and outside the country who stood to fight for the release of my brother," he said.
Frank Edohor, a family friend, had earlier told AFP about the release.
But neither Sanusi Onimisi nor Edohor were able to provide details surrounding the release.
"All I can say is that he has been freed by those who arrested, detained and held him incommunicado for about 11 days. I have not slept well since his arrest," the younger brother said.
Onimisi's case sparked concern from human rights groups, with Amnesty International on Friday urging security forces to disclose his whereabouts.
The 32-year-old works for Nigeria's national electricity firm and was assigned to a sub-station within the presidential compound in Abuja.
The compound is near the Directorate of State Services (DSS) headquarters where the agency said there was an attempted jail break on March 30, sparking a gun battle that killed 21 detainees.
Reports suggested Boko Haram militants were among the detainees trying to escape, but there has been no official confirmation of the group's involvement.
Security forces, including the secret police, have frequently cited national security concerns to justify arresting people who publish sensitive material.
DSS spokeswoman Marylin Ogar did not respond to phone calls seeking comment on Onimisi.