The death toll in a bomb attack targeting the United Nations' offices in the Nigerian capital Abuja rose overnight to 25, medics said Saturday.
Dozens were injured and remained hospitalized, some in critical condition. Police were still declining to give an official number of those killed and injured when a suicide bomber drove an explosives-laden car into the compound, DPA reported.
Unconfirmed reports in the Nigerian media said the number of fatalities could be even higher, as victims were taken to several hospitals and information was being pulled together slowly.
Among the dead were Nigerian workmen, who were involved in a construction project at the UN and several staff members of the organization, including one Norwegian woman.
"Investigations are going on now. I want to assure you that we are going to pursue these people and their group and bring them to book," Police Commissioner Mike Zuokwunor said, according to the Guardian newspaper.
Nigerian President Goodluck Jonathan also pledged to find those responsible for the attack, following condemnation of the attack by UN Secretary General Ban Ki-moon.
The BBC said it received a phone call from a spokesman for Boko Haram, a domestic Islamist group, who claimed responsibility for the attack.
The area around the UN offices, which houses several agencies and was the workplace for about 1,000 people, was cordoned off on Saturday morning.