LAGOS, Nigeria — Days before a car bombing at a United Nations' headquarters in Nigeria that killed 23 people, the country's secret police arrested two men suspected of organizing the attack, authorities said Wednesday, raising questions about why it wasn't averted.
The State Security Service's statement to journalists said it also sought a third suspect they said had "al-Qaida links" and recently returned from Somalia. It offered new evidence that the radical Muslim sect known locally as Boko Haram, which claimed Friday's attack on the U.N., has ties to al-Qaida-affiliated terror elsewhere in Africa.
The agency said it received word Aug. 18 about a possible car bomb attack in Abuja. On Aug. 21, the secret police said it arrested Babagana Ismail Kwaljima and Babagan Mali, two men they said had ties to Boko Haram and were planning the attack.
On Friday, a suicide bomber rammed through two sets of gates to reach the U.N. building's glass reception hall. There, the bomber detonated explosives powerful enough to bring down parts of the concrete structure and blow out glass windows from other buildings in the quiet Abuja neighborhood filled with diplomatic posts.
The agency did not offer details if it shared any of the intelligence with diplomats in Abuja, Nigeria's capital. The security chief for the United Nations previously said it received no specific warning about a coming attack.
The secret police said the two men are being held at a military base.
"The suspects have made valuable statements," the agency said.
Marilyn Ogar, a spokeswoman for the secret police, declined to comment when asked why the agency couldn't stop the bombing or whether it shared information with foreign diplomats.
"I think all the answers to your questions or concerns are in the press statement," Ogar told The Associated Press on Wednesday.
The State Security Service, the agency responsible for domestic intelligence, has operatives who focus primarily on political opposition or secessionists in Nigeria. The agency also routinely detains journalists and government critics.
The agency also has seen criticism in the past from the United States over its conduct. In a diplomatic cable released by the anti-secrecy website WikiLeaks, U.S. officials recounted how secret police operatives nearly let a suspected bomb maker trained by the Somali terror group al-Shabab onto an international flight in Nigeria. Mohamed Ibrahim Ahmed now faces terrorism charges in federal court in New York.
The secret police "not only knew about the Interpol notice, but simply said they did not want to hold him any longer," the cable reads.
Earlier this month, the commander for U.S. military operations in Africa told the AP that Boko Haram may be trying to coordinate attacks with al-Shabab in Somalia and al-Qaida in the Islamic Maghreb, which operates in northwest Africa.
The agency said a third suspect, Mamman Nur, remained at large.
"Investigation has revealed that one Mamman Nur, a notorious Boko Haram element with al-Qaida links who returned recently from Somalia, (worked) in concert with the two suspects (in) masterminding the attack on the United Nations building in Abuja," the agency said in its statement.
Friday's attack was claimed by a sect known locally as Boko Haram, whose name means "Western education is sacrilege" in the local Hausa language. The sect wants to implement a strict version of Shariah law in the nation and has carried out increasingly bloody sectarian attacks targeting the nation's weak central government from its base in northeast Nigeria.
Nigeria, a nation of 150 million people, is split largely between a Christian south and a Muslim north. Unemployment and unceasing poverty, coming despite the nation making billions a year from oil production, has fueled resentment in recent years in the north.
However, moderate Muslims remain horrified of the bombings in the country. The spiritual leader of the nation's Muslims, the Sultan of Sokoto Muhammad Sa'ad Abubakar III, condemned the bombings in a message Wednesday marking the end of Ramadan
"We should not allow our enemies to cause us to commit acts prohibited by our religion and the perpetrators should desist from such acts and rather seek for avenues of dialogue with the leaders on the problems confronting the nation," Abubakar said.