ABUJA, Nigeria — At least 30 people have been killed after gunmen attacked travelers on a major highway in the southeastern part of Nigeria, rights group Amnesty International said.
The rights group said Friday that more than 20 vehicles and trucks were set ablaze during the Thursday attack along the Okigwe-Owerri highway in Imo state. Police confirmed the attack but not the death toll.
No group has claimed responsibility for the attack, but police suspect the Eastern Security Network, the paramilitary wing of the proscribed separatist group Indigenous People of Biafra.
The secessionist campaign in southeastern Nigeria dates back to when the short-lived Republic of Biafra fought and lost a civil war from 1967 to 1970 to become independent from the West African country. An estimated 1 million people died in the conflict, many from starvation.
The rights group said ''international law requires the Nigerian government to promptly investigate unlawful killings with a view to bringing perpetrators to justice.''
One suspect connected to the attack was killed in a joint operation by law enforcement agencies, police spokesperson Okoye Henry said in a statement.
''An intensive manhunt is ongoing to apprehend the fleeing suspects and bring them to justice,'' Henry said.
Two of the group's prominent leaders, Nnamdi Kanu and Simon Ekpa, are in custody in Nigeria and Finland, respectively.
