The United Nations has confirmed the convoy was hit, but has given no details on who carried out the attack or how many people died.
At least 18 of 31 trucks in a United Nations and a Syrian Arab Red Crescent convoy were hit, as well as a Syrian Arab Red Crescent convoy.
A UN representative had showed off the convoy before its journey began.
"Today we are sending humanitarian assistance to Big Urm (Urm al-Kubra). We have, as you can see, we have 31 trucks lined up and ready to go. These trucks are carrying wheat flour, nutrition, medicine supplies, wash supplies and Non-Food Items. All these materials are going to Big Urm to assist 78,000 people."
On the ground after the bombing, a member of the Syrian Civil Defence, a rescue workers' organisation that operates in rebel-held areas, had no doubt as to who was responsible for the attack.
"This is the warehouse of the Syrian crescent. Around this house were 20 vehicles, 20 trucks full of food and flour and medicine and blankets. The regime helicopter targeted this place with four barrel bombs. The Urm civil defence centre responded to this place in order to [medivac] the injured. But the regime also targeted this place again."
It's a claim the Syrian government and Russia deny.
But regardless of who's responsible, there's little doubt about its far-reaching consequences.
The United Nations has suspended all aid deliveries in Syria as an immediate security measure.
The bombing has been described as an unacceptable and flagrant breach of international humanitarian law.
Benoit Carpentier, from the Red Crescent, says it may ultimately end up costing more people their lives than just those who died in the bombing.
"Failing to protect humanitarian workers and structures might have serious repercussions on ongoing humanitarian operations in the country, hence depriving millions of people from aid essential to their survival."
The UN says if the attack is found to be deliberate, then it's a war crime.
It's claimed everyone knew about the aid convoy and had given it permission.
United Nations spokesperson Jens Laerke says the suspension of aid convoys is only a temporary measure.
"Other convoy movements in Syria have been suspended for the time being, pending further assessment of the security situation. However, we remain committed to stay and deliver to everybody in need."
The Syrian Observatory for Human Rights claims there have been 35 strikes in and around Aleppo since the seven-day truce period ended.
Russia claims it's ready to keep working on the implementation of the ceasefire.
But these events appear to signal that the latest attempts to end Syria's five-and-a-half-year internal conflict have collapsed, or are close to collapsing.
And the events are sure to be a topic of discussion as world leaders gather for a meeting at the United Nations in New York.
