Henry Okah is believed to be a top member of the group that said it bombed Nigeria 's capital . Six people have been arrested in Nigeria in connection with the attack . MEND , which claims responsibility , says it gave the president notice of bombings . MEND , which represents militants in the oil-rich Niger Delta , is an umbrella organization of several rebel groups . The president said the attack was an attempt to disrupt national celebrations .
Henry Okah is believed to be a top member of the group that said it bombed Nigeria 's capital . Six people have been arrested in Nigeria in connection with the attack . MEND , which claims responsibility , says it gave the president notice of bombings . The president said the attack was an attempt to disrupt national celebrations .