The U.S. is offering a $5 million reward for information that leads to the arrest or conviction of the militants who committed or aided in the deadly Oct. 4, 2017, attack on a joint U.S.-Nigerien military patrol that left four U.S. soldiers dead.

The U.S. Department of State’s Rewards for Justice Program is also offering a $5 million reward for information or location of Adnan Abu Walid al-Sahrawi, the leader of the ISIS offshoot known as Islamic State in the Greater Sahara, according to a news release.

The ISIS affiliate in West Africa claimed responsibility for the deadly attack that overwhelmed an American special operations team and roughly 30 Nigerien troops who accompanied the patrol near the village of Tongo Tongo, Niger.

The patrol was pursuing an ISIS commander named Doundoun Cheffou when it was ambushed resulting in the deaths of four American soldiers, Sgt. First Class Jeremiah Johnson, Staff Sgt. Bryan Black, Staff Sgt. Dustin Wright and Sgt. La David Johnson, who were all assigned to Army Special Forces Operational Detachment Alpha 3212.

Two years later, how one soldier lost trust in the Army after the Oct. 4, 2017, Niger ambush Alan Van Saun, the company commander for Alpha Company at the time of the ambush, detailed how his trust in the Army deteriorated because of the incident in an op-ed penned for the New York Times, marking the two-year anniversary of the attack.

An investigation into the deadly firefight found a number of issues wrong with mission planning prior to the patrol, namely that the team was not clear in its concept of operations paperwork that they intended to pursue Cheffou.

The team was not authorized to conduct or perform capture or kill missions. However, the investigation noted that the officers who filed the paperwork were not being deceptive.

“The direct cause of the enemy attack in Tongo Tongo is that the enemy achieved tactical surprise there, and our forces were outnumbered approximately three to one,” said AFRICOM’s former chief of staff, Army Maj. Gen. Roger Cloutier, who led the investigation, according to Army Times.

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FILE - These images provided by the U.S. Army show, from left, Staff Sgt. Bryan C. Black, 35, of Puyallup, Wash.; Staff Sgt. Jeremiah W. Johnson, 39, of Springboro, Ohio; Sgt. La David Johnson of Miami Gardens, Fla.; and Staff Sgt. Dustin M. Wright, 29, of Lyons, Ga. All four were killed in Niger, when a joint patrol of American and Niger forces was ambushed on Oct. 4, 2017, by militants believed linked to the Islamic State group. The Mauritanian Nouakchott News Agency reported Friday, Jan. 12, 2018 that Abu al-Walid al-Sahrawi with the self-professed IS affiliate claimed responsibility for the Oct. 4 ambush about 120 miles (200 kilometers) north of Niger's capital, Niamey. (U.S. Army via AP)

A number of people were reprimanded following the ambush including the commanding officer of Special Operations forces in Africa Maj. Gen. Marcus Hicks, among other officers.

The fallen soldiers in the Niger ambush were posthumously awarded medals for valor.

Wright’s family was presented with the Silver Star in August.

Sgt. La David Johnson’s family was also presented with a Silver Star. He was a mechanic assigned to the special operations team.

play_circle_filled Fallen soldiers of Niger ambush receiving Silver, Bronze Stars this week Valor awards go to four U.S. troops with Army Special Forces ODA 3212 who were killed in the ambush.

Sgt. First Class Jeremiah Johnson and Staff Sgt. Bryan Black were posthumously awarded Bronze Stars.

The State Department release said Abu Walid — the leader of the West Africa ISIS affiliate — swore allegiance to ISIS in 2015, and that the group has carried out several attacks under his leadership.