Nigerian authorities have arrested the brother of former militant leader Henry Okah, on suspicion that was involved in twin car bombings that killed 12 people.
A security source told reporters Sunday that Charles Okah was arrested in Lagos and taken to the capital, Abuja. They say he is suspected of helping to fund the October 1 bombings.
The source also accused Charles Okah of sending out e-mails for the militant group MEND, which claimed responsibility for the attacks. The group's e-mails always carry the name of Jomo Gbomo, and are issued from a Yahoo account.
Henry Okah was arrested in South Africa earlier this month and charged with terrorism for allegedly masterminding the bombings. Okah, who is believed to be MEND's former leader, has denied any involvement.
Nigerian authorities have arrested nine other people in connection with the bombings.
MEND - the Movement for the Emancipation of the Niger Delta - says it is fighting for a fairer distribution of wealth in the oil-rich Delta region.
The group has claimed responsibility for dozens of attacks and kidnappings in southern Nigeria. Many of the group's fighters accepted a government amnesty last year.
Some information for this report provided by AP and Reuters.