ABUJA, Nigeria (AP) -- Dozens of people are feared dead in an explosion that blasted through a busy commuter bus station on the outskirts of Nigeria's capital, Abuja, before 7 a.m. (0600 GMT) Monday as people were traveling to work.
Reporters saw rescue workers and police gathering body parts and ambulances rushing the wounded to the hospital.
Suspicion immediately fell on the Boko Haram terrorist network that has been threatening to attack the capital, in the middle of the country and hundreds of miles from its traditional base in the northeast, where it has killed nearly 1,500 people this year. The militants' violent campaign poses the greatest threat to the cohesion and security of Africa's biggest oil producer as the country prepares for elections in February 2015.
Monday's blast ripped a hole 4 feet deep (1.2 meters) in the ground of Nyanya Motor Park about 16 kilometers (10 miles) from the city center and destroyed more than 30 vehicles, causing secondary explosions as their fuel tanks ignited and burned.
"I can't count the number of people that died. They took them in open vehicles. People were running and there was confusion," said civil servant Ben Nwachukwu.
Security personnel belatedly cordoned off the area and a bomb detonation team was combing it for secondary explosives, a common occurrence here.
The explosion appeared to come from a vehicle at about 6:45 a.m., according to the National Emergency Management Agency. "It affected quite a number of people because it was still very early in the morning and there was a lot of traffic," according to the agency's Air Commodore Charles Otegbade. He did not give a death toll.
There was no immediate claim for Monday's rush-hour explosion though bus stations are a favored target of Nigeria's Islamic extremists.
The Boko Haram terrorist network claimed responsibility for a 2011 suicide bombing by two explosives-laden cars that drove into the lobby of the United Nations office building in Abuja. It killed at least 21 people and wounded 60.
Last week, Boko Haram suspects detained at the State Security Service headquarters in Abuja, next door to the residence and office of President Goodluck Jonathan, staged a failed jailbreak in which it is suspected that they had outside help. The agency said 21 detainees were shot and killed and two agents wounded in a shootout that lasted more than two hours.
The militants are blamed for attacks in northeast Nigeria that have killed more than 50 people in the past five days, including eight teachers living at a boarding school that had been closed because of frequent attacks on schools in which hundreds of students have died.
Boko Haram -- the nickname means "Western education is forbidden" -- has been attacking schools, villages, market places and military barracks and checkpoints this year in increasingly frequent and deadly attacks. Its mission is to force an Islamic state on Nigeria, Africa's most populous nation of some 170 million people divided almost equally between Muslims living mainly in the north and Christians in the south.
The military has claimed that it has the extremists on the run with near-daily air bombardments and ground assaults on hideouts in forests and mountain caves along the border with Cameroon.