The IDF has revealed that it had captured footage of an Israeli hostage calling for help after the terrorists holding him and two other men were killed — but the camera was not analyzed until after soldiers mistakenly shot them dead days later.

Golani Brigade commandos encountered a group of Hamas terrorists who fired at them from a building on Dec. 10, the Times of Israel reported, citing a military investigation into the deaths of the hostages.

During the firefight, a dog with the elite Oketz unit was sent into the building, where Yotam Haim, 28, Samer Talalka, 22, and Alon Shamriz, 26, were being held.

Before being killed by the soldiers, the terrorists gunned down the canine, but the GoPro camera it was carrying continued to operate and recorded the voice of a hostage believed to be Shamriz, according to the outlet.

“Help!” he shouted in Hebrew, adding that there were other hostages with him who also were not seen in the footage.

The video from the fallen dog was not being monitored live by the troops, who left the animal at the location while they engaged other targets, the Times of Israel reported.

It was only on Dec. 18 that the IDF reviewed the camera and discovered its alarming contents, according to the military probe.

The Golani forces believed they had heard “Save us!” and “hostages” during the gun battle, but they believed the calls came from the terrorists using them as a ruse.

IDF chief of staff Lt. Gen. Herzl Halevi has ordered an investigation into the footage as part of the overall inquiry into the mishap, Israel Hayom reported.

The three men’s families have been updated on the latest development, which sheds more light on the actions they took to alert the IDF about their presence as they tried to avoid being recaptured over the next five days.

The hostages had used leftover food to write “SOS” and “Help, 3 hostages” on a white cloth they hung on a building in Gaza City’s Shejaiya neighborhood.

“Based on the investigation of the incident in the field, it appears that the three abductees were in the building where the signs were located, at least some of the time,” IDF spokesperson Rear Adm. Daniel Hagari wrote on X.

The shirtless trio later waved a white flag as they approached Israeli soldiers, one of whom perceived them as a threat and opened fire against army regulations.

Two of the hostages were immediately killed while the third returned to the building after being wounded, officials said.

When a cry for help was heard in Hebrew, the battalion commander ordered his troops to cease fire, but the wounded man also was shot and killed when he came out, a military official said.

Haim and Shamriz were abducted from Kibbutz Kfar Aza during Hamas’ terror attack on southern Israel on Oct. 7. Talalka was taken from Kibbutz Nir Am.

As a result of the friendly-fire tragedy, the IDF sent new protocols to soldiers for the possibility of additional hostages managing to flee captivity.

The Post has reached out to the IDF for comment.