No one has claimed responsibility for the bombing in Nigeria that killed at least 72 people and injured 169 others.
Nevertheless, Nigerian President Goodluck Jonathan said the evidence suggests the attack was the work of the Boko Haram terrorist group.
The massive explosion, the deadliest ever to hit the capital city of Abuja, occurred at a bus station during morning rush hour. Some witnesses said they initially thought a fuel tanker had exploded.
Victor Oladokun, Nigerian CEO of 3D Global Leadership, was in Abuja at the time of the attack. He said a fearful, somber mood prevails in the capital city because no attack has occurred there for the past four years.
"There has been a sense that Abuja is secure; Abuja is pretty much impregnable. That sense of hope and that sense of anticipation has been shattered right now," Oladokun said.
Some people speculate the bomb was hidden in the ground because the blast left a crater more than four feet deep and spread hot shrapnel across a wide path, slicing into the flesh of nearby commuters.
However, government investigators insist a suicide car bomber caused the deadly explosion.
Oladokun said most Nigerians believe the attack was the work of Boko Haram terrorists.
"What is a little bit disconcerting, I guess confusing for a lot of Nigerians at the moment is there is no rhyme or reason to all of the attacks," Oladokun said.
The bombing indicates that Boko Haram's terrorism may now be entering a new phase - one where public facilities are targeted in addition to churches and schools.
"We need to pray that peace will reign, that the attackers will be exposed and apprehended, and that sanity and peace be restored in Nigeria," Oladokun said.