Abuja - Nigeria on Friday urged delegates due for the World Economic Forum (WEF) in Abjua next week "not to let terror win" by staying away after a second bombing in the capital in less than three weeks.
A suspected car bomb killed 19 people and wounded 34 on Thursday night in the suburb of Nyanya, about 8 km from Abuja city centre and next to the bus station where a rush hour bomb attack killed 75 people on April 14.
The bombs, along with the abduction of 200 girls from a secondary school in Chibok near the Cameroon border, threaten to overshadow the WEF conference's emphasis on Africa's positive growth story.
The girls, who were taking exams, were taken away on trucks on the same day as the bus station bombing. Both attacks showed the powerlessness of Nigerian security forces to protect civilians against the militant Islamist group Boko Haram.
President Goodluck Jonathan's government will mount a huge security operation to protect the WEF scheduled for next Wednesday and Thursday.
A regional replica of the Davos, Switzerland, event, it will bring together international leaders, policy-makers, entrepreneurs and philanthropists.
"We want to state categorically that the President Goodluck Ebele Jonathan administration will not be diverted nor will it give in to these neferious acts of terrorism," Finance Minister Ngozi Okonjo-Iweala said in a statement on Friday.
"The goverment has taken the strongest measures to ensure a safe forum. We ask participants not to let terror win."
Despite the repeated assurances on security, there were signs not all delegates were convinced that Nigerian authorities could keep the capital safe during the event.
Fernando de Sousa, General Manager of Microsoft Africa Initiatives, cancelled his trip "for security reasons following the bombings in Abuja", a PR company representing the firm said.
Jonathan met his security chiefs on Friday, directing them to "increase surveillance and expedite investigation into the explosion to ensure that those behind the heinous act are ... brought to justice," a statement from his office said.
It added that "intensive aerial surveillance by the Air Force has been carried out in all the routes leading into and out of Chibok up to the Chad and Cameroon borders," in search of the kidnapped schoolgirls.