Originally published on August 19, 2013

This animation was created using the most complete information available as of 9 a.m. GMT.

At least 35 protesters detained by police were killed on Sunday while being transported to Abu Zaabal prison. They were being transported in a convoy of police vehicles carrying 600 detainees. Accounts differ as to how the men were killed. The Egyptian Interior Ministry claimed that the prisoners took a police officer hostage, and then were suffocated with tear gas which the police fired in an attempt to free the captured officer.
That account conflicts with the one reported by the Egyptian MENA news agency. Their report says the prisoners staged a fight in order to make the convoy stop on the road before reaching Abu Zaabal prison. When the convoy stopped, gunmen attacked the trucks, allowing the prisoners to take a police officer hostage. The 35 men were killed in the ensuing firefight, not by suffocation from tear gas, according to MENA.
A third account given to Al Jazeera by an unnamed source differed from that of MENA in that it does not mention an attack by gunmen, but agrees that the convoy was forced to pull over and a police officer was captured by the prisoners after they staged a fight.
In an English statement released on their website, the Muslim Brotherhood described the deaths of the prisoners as cold-blooded killings targeting coup opponents and put the number of dead at 52, not 35.