LAGOS, Nigeria (Agencies) - A Nigerian military attack using heavily armed soldiers and aerial bombing runs has killed as many as 150 people in the oil-rich southern delta, a human rights activist has said. Oghebejabor Ikim, national co-ordinator for the Forum of Justice and Human Rights Defence, said civilians had suffered a heavy toll in the military operation that began on Wednesday. He did not say how many of the 150 dead were civilians, but said militants left the area before the offensive began. The attacks on a village in the Niger Delta continued on Friday as the military tried to kill or capture a militant called John Togo who officials said gave up on a government-sponsored amnesty programme. The amnesty for militants brought an uneasy calm to a region vital to US oil supplies, which is now threatened by new militant attacks and government offensives that put civilians at risk. I can describe it as a killing spree of innocent civilians, Mr Ikim said. Houses have been burnt. Women are raped. There are killings. Is that how to get at John Togo? A military spokesman said the operation is ongoing, but would not comment further. The military has declined to offer a death toll for the operation targeting the village of Ayakoromo and surrounding communities. An independent assessment of the damage and casualties from the attack has yet to be done. The Nigerian Red Cross and other activists have been unable to reach the targeted communities as the military has sealed off the winding muddy creeks that lead to the region. Activists say they continue to see smoke rising from the area and can hear gunfire. Video aired on Thursday afternoon on state-run Nigerian Television Authority showed soldiers in flak jackets and helmets travelling by boat through the muddy creeks. The network also showed images of what appeared to be suspected militants in custody and of a soldier setting a hut ablaze with a lighter. Lieutenant Colonel Timothy Antigha, a military spokesman, previously said soldiers recovered anti-aircraft guns, rocket-propelled grenades, automatic rifles and dynamite from the three camps targeted in the attack. However, it appears that soldiers have yet to apprehend Togo. Casely Omon-Irabor, a lawyer representing Togo, said that the militant and his fighters were far away in the high seas and not in the region being attacked. The lawyer said the government had planned a meeting to negotiate a settlement with Togo, but instead launched a military operation against him. I do not see any reason why we are calling for truce and trying to get peace and yet a party for that peace has breached that agreement and gone into war again in the creeks, Mr Omon-Irabor said.