Vets ask Pentagon leader to take new look at Niger probe after the '3212 Unredacted' film aired on Hulu.

ABC News probes the mystery behind the 2017 deaths of four Green Berets in Tongo Tongo, Niger, in the documentary "3212 UN-REDACTED," coming Nov. 11 to Hulu.

ABC News documentary "3212 UN-REDACTED" probes the deaths of four soldiers killed in a 2017 ISIS ambush. Their families accused the Pentagon of lies and betrayal

The families of the four American Green Berets killed in a 2017 ambush by ISIS in Niger accused the Pentagon of allegedly covering up the details of their deaths and mission.

ABC News’ Ian Pannell spent years digging into why American soldiers were killed in October 2017, and the decisions and mistakes made after a lengthy Pentagon investigation.

The families of four U.S. soldiers, who were killed in the 2017 Niger ambush, are blasting the Pentagon's decision not to punish higher-ranking officers for their role.

A four-star general is to review the investigation into the deadly, 2017 attack in Niger that killed four soldiers and decide if more disciplinary actions are warranted.

Gen. Thomas D. Waldhauser gave remarks following the investigation of the Oct. 4, 2017, attack that killed four U.S. soldiers.

A military probe found failures led to the ambush of American soldiers in Niger.

Four Army special operations soldiers killed in action during an ambush in Niger last October were part of a largely inexperienced and lightly-armed team.

The series "Chain of Command" airs on the National Geographic channel.

Johnson and three other U.S. soldiers were killed in October.

The U.S. soldiers were ambushed by an ISIS-affiliated group in Niger in October.

Sources say Nigerien and U.S. forces asked for more support but the request was refused.

The operation in Niger was a kill or capture mission.

Officials say a military operation will take place soon against those responsible for the attack.

Senior intelligence officials say three of the soldiers died after their vehicle was hit with mortar and gunfire.

Myeshia Johnson backed up what a congresswoman said she overheard on the call with the president.

“It’s our responsibility, and we should be embarrassed, at best," he said.

The Oct. 4 assault left four U.S. soldiers dead.

Four U.S. soldiers were killed in an ambush earlier this month.

U.S. intelligence officials are examining video of a militant group, looking for clues to identify who ambushed and killed four U.S. soldiers.

U.S. intelligence officials are examining the video looking for clues to the identity of the men who ambushed and killed four U.S. special operations soldiers earlier this month.

U.S. intelligence officials are examining video of a militant group in Niger, looking for clues to the identity of the men who ambushed and killed four U.S. soldiers.

ABC News has learned chilling new details about the Niger mission gone wrong.

The video was provided to ABC News by a former US military expert on West Africa who says it came from villagers in the vicinity of the attack that left four U.S. soldiers dead.

The video, which is currently being examined by U.S. intelligence officials, was provided to ABC News by a former US military expert on West Africa who says it came from villagers in the vicinity of the attack that left four U.S. soldiers dead.

The statement came after the U.S. provided a timeline of the deadly the ambush.

Trump's promised $25,000 check from July finally arrived.

The special operations soldiers started out on a routine reconnaissance mission but were later told to kill or capture a top ISIS target, a senior intelligence official told ABC News.

We are learning how long after soldiers came under fire and called for backup that help arrived.

Myeshia Johnson spoke to ABC News about her husband's death

Myesha Johnson said she wasn't allowed to see her husband's body.

La David Johnson was killed in an ambush.

McCain was a guest on "The View."

President Donald Trump today contradicted the account of a fallen soldier's widow, arguing that he said her husband's name "without hesitation" when he called to offer condolences Tuesday.

"My friends we should not be fighting about a brave American who lost his life. That should not be the topic of discussion in America today," Senator John McCain, R-Ariz., said today on 'The View.'

Four U.S. soldiers died in an ambush in the country earlier this month.

Two weeks later, the details of the deadly incident remain unclear.

U.S. Army Sgt. La David Johnson, who was among four American service members killed in Niger earlier this month, was laid to rest in Florida on Saturday.

New details about how the Niger ambush unfolded have emerged

Myeshia Johnson, the widow of Sgt. La David Johnson, tells "GMA" what she recalls President Trump said to her on the phone and what she wants to know about the ambush in Niger that killed her husband.