NIAMEY/WASHINGTON (Reuters) - A month after an Islamist ambush in Niger killed eight U.S. and Nigerien troops, the two sides  officials still cannot agree on the sequence of events leading to the incident or even, possibly more importantly, on the nature of the mission itself. Four soldiers from each nation were killed when a joint patrol was attacked on Oct. 4 by dozens of militants with machine guns and rocket-propelled grenades. The incident drew attention to the little-known U.S. military presence in Niger at a time when many Americans are weary of U.S. involvement in conflicts abroad and Nigeriens are chafing at the growing presence of foreign troops on their soil. The United States has 800 soldiers operating in the largely desert West African nation, more than France, which has 4,000 in the wider Sahel trying to tackle Islamist militancy. The main U.S. base in Africa is in Djibouti, which supports about 4,000 personnel. A Pentagon investigation into the incident, led by a two-star general from U.S. Africa Command, may take weeks. The Pentagon says it has not settled on any final version of events. Through interviews in Niger s capital Niamey and Washington, Reuters has tried to piece together the events of Oct. 3 to Oct. 6, when the last U.S. soldier s body was recovered. Accounts by Nigerien and American officials differ over the mission s objectives, and whether and how they may have changed.  The one consistent thread is that they appear to have been woefully unprepared for their enemy. U.S. and Niger officials agree that on Oct. 3, 12 U.S. Special Forces and 30 Nigeriens left Niamey and headed north to the Mali border. Twenty six similar patrols had taken place in the area in the past six months without enemy contact, the Pentagon said. After that, the stories of the two sides diverge.  It was an intelligence mission but also a mission of an operational nature,  Niger Interior Minister Mohamed Bazoum told Reuters in an interview.  It was in a zone that was considered safe, not enemy territory.  Specifically, the mission aimed to detain and question a suspected recruiter for Islamic State in the Greater Sahara, an Islamic State affiliate, according to a senior Nigerien security source with knowledge of the operation and two mid-level government sources, all of whom declined to be named.  The senior source said the mission was thought low enough risk that they had no armored vehicles or body armor. U.S. officials vehemently contradict this account.  The service members involved in this unfortunate incident were unequivocally not directed to do a  kill or capture mission . They were on a reconnaissance mission,  the Pentagon said in statement sent to Reuters on Thursday. It said it would provide more details once the investigation is complete. All three Nigerien sources said the target was a mid-ranking commander called Doundou Chefou who was recruiting disgruntled youths from the Fulani ethnic group along Niger-Mali border. Chefou commanded Islamic State fighters affiliated to the movement led by an Arabic-speaking north African called Adnan Abu Walid al-Sahrawi, the Nigerien sources said. According to the senior Nigerien security official, the team initially sought Chefou out near a remote border village on Oct. 3. They found a militant camp there but no fighters, he said. After that, Nigerien intelligence officials on the team received fresh orders from their headquarters to pursue him in the village of Tongo Tongo, so they stayed the night nearby, the official said. Three U.S. officials, speaking on condition of anonymity, said that while it is true the team was given an additional task mid-mission, it was never in pursuit of a militant. The U.S. officials said their soldiers were asked to work with the Nigerien troops to be on standby to help a second U.S. military team whose mission was indeed to pursue a militant. That mission was called off, however. It is unclear when or why.  Did the mission change? That s one of the questions being asked. I can t tell you definitively the answer to that question,  General Joseph Dunford, chairman of the Joint Chiefs of Staff, said last month. The U.S. officials said the first team was asked to gather intelligence on the militant. The Americans could do this under  U.S. military rules of engagement that allow American forces to accompany partner forces only when the chances of enemy contact are  unlikely.  Asked about the existence of a second mission, none of the Nigerien sources were aware of it. U.S. and Nigerien officials agree the team was ambushed after they met local leaders in Tongo Tongo on Oct. 4. One of the Nigerien government sources said the militants first came with just a few gunmen with AK47s on motorbikes to slow them down, and later brought out heavier 12.7mm machine guns, sniper rifles and rocket-propelled grenades. That might explain why the team took an hour to call for help - one of the issues that has most disturbed senior Pentagon officials - because the initial attack may have only involved light arms. A few minutes after the team called for air support, a surveillance drone appeared, providing a live feed, but it took another hour before French military aircraft arrived. They were unable to drop bombs because of how close the fighting was, diplomatic sources have said. One U.S. official said at least some of the four U.S. soldiers killed were then separated from the convoy. They included Sergeant La David T. Johnson, whose body was not recovered for two days. It is unclear why. It is unlikely the United States will back away from Niger because of its central location in the Sahel and because of the proliferation of militant groups around it, including Nigeria s Islamic State-linked Boko Haram and al-Qaeda affiliates. Several current and former U.S. officials with Africa experience said they expected U.S. military focus on the Sahel to grow, not decrease. Retired general Donald Bolduc, who led U.S. special operations in Africa until June, said the military should retain a small  footprint  in Africa but needed more intelligence and surveillance resources and medical and air support. While the most assets have gone to the Middle East and Afghanistan,  there needs to be ... a different perspective on how we allocate the resources between theaters,  he said. He expressed surprise at the idea that the unit which was ambushed had been redirected to focus on a militant leader. Senior militant leaders are normally well protected, Bolduc said, with rings of security guards and layers of militants who communicate with one another via radio.  I m as confused about it as you are,  he said.  That s not how it s done. ... The resources and planning didn t seem to be there for that kind of operation.  