Pentagon has identified the fourth soldier killed in the West African country of Niger on Wednesday, as Army Sergeant La David Johnson, was 25 years of age, Abc News reported.

Johnson's body was discovered by Nigerian troops, 48 hours after he was reported missing. According to US military officials, his body was found in a remote area of Niger. A Search And Rescue operation had been launched by a joint US, Nigerian, and French force, with the hope of finding Sgt. Johnson alive.

Enemy fire killed Sgt. Johnson and three of his colleagues according to the Pentagon.

After the attack, Johnson could not be accounted for which prompted the search and rescue mission. The army thought the attackers had captured him and electronic signals showed that he was somewhere out in the field, alive.

Ambush

US military officials told ABC News that a 12-member US team was attacked by around 50 fighters as they left a venue for a meeting. The team came under heavy fire from the attackers but managed to take cover and return fire, killing some of the attackers in the ensuing exchange.

It was at this point officials believe that Johnson was separated from his colleagues under unclear circumstances. None of Johnson's colleagues witnessed his capture or him being taken away by the enemy, and this when the massive search effort begun.

A spokesman for Africa Command, US Col. Mark Cheadle, said Johnson's body was found 'not far' from where the attack occurred.

The Nigerian troops who found Jonson's remains then handed them over to a team of US Special Operation Forces. The body was then flown to Niamey, Niger's capital, for identification.

Other personnel killed

On Friday, the military released a statement identifying the three soldiers who were also killed in the ambush as Staff Sgt. Justin Wright, Staff Sgt. Bryan Black, both Green Berets, and Staff Sgt. Jeremiah Johnson. All three were based at Fort Bragg to the 3rd Special Forces Group, Airborne Division.

Nigerian security officials said they also lost five of their soldiers who were part of a platoon accompanying the US team, during the ambush.

According to a statement from Africa Command, which oversees military operations in Africa, there are around 800 US troops in Niger. The US has maintained a military presence for the past five years according to ABC News.

The US plays an assistance and advisory role while also providing training to West African troops fighting extremists in the region.