By Paul Brown & Jemimah HerdBBC Verify

Warning: This article contains details that some may find distressing

Reports first emerged on Friday evening of a strike on a convoy of vehicles heading towards southern Gaza. These vehicles were carrying civilians, who were fleeing northern Gaza after the Israel Defense Forces (IDF) issued an evacuation order.

Videos showing the carnage at the scene emerged shortly afterwards.

BBC Verify has confirmed the strike occurred on Salah-al-Din street, which is one of two evacuation routes from northern Gaza to the south.

The Palestinian Health Ministry says 70 people were killed at the scene, and Hamas blamed Israel for the attack. The IDF has told the BBC it had no involvement in the incident.

What does the footage show?

The longest video we have verified is too graphic for us to show. It's a scene of total carnage. Men are seen running, yelling prayers and laments into the smoke-filled air. Sirens and car alarms howl throughout.

As the camera moves along the scene, the extent of the devastation becomes clear. Bodies, twisted and mangled, are scattered everywhere.

Later, the broken body of a small child - a boy, dressed in shorts and a T-shirt - is seen lying on a truck, his head twisted awkwardly towards the camera.

We counted at least 12 dead bodies at the scene. Some of them women and young children.

Other footage shows the bodies of victims lying in the street, and vehicles on fire.

Verifying the aftermath

A number of videos have now emerged on social media showing the immediate aftermath of the strike.

Local media reports said the attack took place on Salah al-Din road, a major highway that runs north to south across the strip, and one of just two evacuation routes for civilians living in the north.

The road was full of traffic all day on Friday following Israeli warnings to leave the area.

Building on work from open source analysts, such as Chris Osieck, we began by verifying the first video that shows the aftermath of the attack. We focused our attention on this 45km-stretch (28 miles) of road, beginning with the north, as that was where the convoy was likely to have set off from.

The video had a number of key details - buildings, road markings, signs - that offered clues to the location.

Using satellite imagery we looked along this road, searching for areas that matched the details we had seen in the video. We placed the location a few kilometres from the southern outskirts of Gaza City.

We performed a reverse-image search on certain keyframes in the footage to ensure that the material was new, and had not been reposted from an older incident.

Finally, we used online tools that identify the angle of sunlight and length of shadows to work out that the footage was filmed around 17:30 local time (14:30 GMT) on 13 October.

Having established the key details, we were then able to identify common features in other footage claiming to show the incident, including a video shot from about 100 meters away which shows burning vehicles.

We spoke to several weapons experts but they said it is hard to tell what caused the explosion based on the videos of the aftermath.

Before the attack

Another video was circulating on X (formerly known as Twitter) early on Saturday morning, showing a convoy in Gaza with about 30 people on board.

Online software which analyses the angle of shadows tells us the video was likely filmed between 15:30 and 17:20 local time on Friday, before the convoy blast incident.

It was filmed close to the location where the aftermath of the strike was recorded, and there were suggestions that it showed the same truck pictured at the scenes with bodies lying across it.

However, putting images of the two trucks side by side suggests they are not the same vehicle. The undercarriages are different - with one truck having two rectangular boxes, and the other having one. There are also other visual differences.

More on Israel Gaza war

The IDF says its enemies are trying to prevent civilians leaving the north.

BBC Verify will continue to monitor the situation and report any updates.

This piece was first published on 15 October and has since been updated.

Additional reporting by Rollo Collins and Benedict Garman

More on Israel Gaza war

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