[20][21] As traditionally performed, the Hajj consists of a series of rites including the Stoning of the Devil (Arabic: رمي الجمرات ramī al-jamarāt)[22][23] which is done at the Jamaraat Bridge in Mina, a district a few miles east of Mecca.

[24][25] The 2015 Hajj occurred during a time of regional turmoil (including wars in Syria, Iraq, Yemen, and Libya), the highest temperatures in Mecca in 20 years and the threat of MERS.

[29] The Saudi Arabian government has been spending $60 billion to expand the Grand Mosque which houses the Kaaba, and has deployed 100,000 security forces and 5,000 CCTV cameras to monitor the crowds.

[31] According to a statement by the Saudi civil defence directorate, the crush occurred Thursday 24 September 2015 at 09:00 Mecca time (06:00 UTC) at the junction between street 204 and 223 as pilgrims were en route to the Jamaraat Bridge.

What happened was that a group of pilgrims on buses were allowed to descend onto the pathways that lead to the Jamarat Bridge at a time that wasn’t allocated to them," Al Arabiya News Channel's correspondent in Mina, Saad Al-Matrafi said.

"[83] One day after the Mina crush disaster,[84] Saudi media publicized a statement by the Grand Mufti of Saudi Arabia, Abdul-Aziz ibn Abdullah Al ash-Sheikh, exonerating Crown Prince Muhammad bin Nayef (known as "MBN") from responsibility for the disaster, as his title of Minister of the Interior holds him accountable for safety issues at the Mecca shrine.

The Grand Mufti's statement, which characterized the incident as "beyond human control", "inevitable", and attributable to "fate",[84] immunized MBN against possible domestic criticism.

[89] On the day of the disaster, the Saudi Civil Defence directorate stated that casualties were of multiple nationalities and announced the deployment of 4,000 personnel to the crush site alongside 220 emergency response units.

[90] By 2 October 2015, the Saudi Arabia Health Ministry stated they had completed the DNA profiling of all unidentified pilgrims who were killed or injured in the crush.

[...] About 5,000 people coming from the same direction were not aware of the road block in front, which resulted to a tight and stationary human traffic, which made it very difficult for us to even stand.

[116] Ishaq Akintola, a Nigerian Professor of Islamic eschatology, gave an eyewitness account of the disaster: "on that fateful day, we found out that some of those who had thrown their own stones made a U-turn instead of moving ahead to take a detour.

[117] In a statement released by the Saudi embassy, Foreign Minister Adel al-Jubeir stated, "The Custodian of the Two Holy Mosques has directed to launch a thorough investigation that will be transparent [...] We will reveal the facts when they emerge, and we will not hold anything back.

Saudi newspapers reported that on 18 October 2015 bin Nayef talked to the investigators and urged them to "continue their efforts to find the causes of the accident, praying to Allah Almighty to accept the martyrs and wishing the injured a speedy recovery".

[120][needs update] Prompted by difficulties in identifying bodies after the Mina disaster, Saudi Arabian Deputy Minister of Health, Hamad Al-Duwailie, announced plans to require all Hajj pilgrims to wear an electronic bracelet containing identity information.

[121] In January 2016, the Saudi Shura Council recommended "raising the capacity of roads leading to the Jamarat facility, and to the accommodation areas in Mina" as well as more studies on Hajj-related transportation flow.

[...] And it should be empowered by the subpoena power and charged to conduct a comprehensive, systematic and interdisciplinary investigation by employing the system-oriented, robust 'AcciMap' methodology to write the most technically-sound report on the root-causes of this tragedy".

[123] Amer Shalaby is a Professor of Civil Engineering at the University of Toronto's Transportation Research Institute, former Hajj pilgrim, and consultant to Saudi government on crowd management.

Shalaby, who specializes in transportation planning for large-scale events, proposes using "smart phones and other static and dynamic sensors" to provide authorities real-time information that could identify potential trouble places during the Hajj.

[125] After the Mina disaster, many of the world's politicians sent messages of sympathy and consolation, including German Chancellor Angela Merkel, Qatari Prime Minister Abdullah bin Nasser bin Khalifa Al Thani, King Mohammed VI of Morocco, Kuwaiti Emir Sabah Al-Ahmad Al-Jaber Al-Sabah, Pakistani President Mamnoon Hussain, and Tunisian President Beji Caid Essebsi.

[188][189] Politicians and religious leaders in a number of Muslim countries have cited the 2015 Mina Crush disaster as reason for control of the Hajj be given either to a different nation or to a pan-Islamic organization.

[190] Mohammad Emami Kashani, an Iranian Ayatollah, also demanded transfer of the control of the Hajj to the OIC,[191] stating "Saudi Arabia is incapable of organising the pilgrimage.

[187] In 2016, supreme leader of Iran, Ayatollah Ali Khamenei sent a global message via his website severely criticizing Saudi rulers[193][194][195] for what he called "the crimes they have caused throughout the world of Islam,"[196] and asked they be held responsible.

[198] He demanded reconsidering the management of two holy places and the issue of hajj due to what he described as "Saudi rulers' oppressive behavior towards God's guests," referring to 2015 Mina disaster.

[203] Rouhani suggested that the Mina crush could be the result of the Saudi government moving their best troops to Yemen, and leaving Hajj crowd control to less experienced soldiers.

[203] Amid deteriorating diplomatic relations and after months of negotiations concerning visa requirements and safety logistics, in May 2016 Iran suspended participation with the upcoming Hajj scheduled for September 2016.

"[188] According to reports, favored to replace Salman is his younger brother, Prince Ahmed bin Abdulaziz, another son of Saudi Arabia's founding king Ibn Saud, and former Interior Minister.

[188][213][215] But as the holder of the royal title "Custodian of the Two Holy Mosques", King Salman has been embarrassed by the twin disasters that bracketed the 2015 Hajj season—the Mecca crane collapse and the Mina Crush.

[217] Use of the word "stampede", says Edwin Galea of the University of Greenwich, is the result of "pure ignorance and laziness ... it gives the impression that it was a mindless crowd only caring about themselves, and they were prepared to crush people.

[28] "If you look at the analysis, I’ve not seen any instances of the cause of mass fatalities being a stampede," says Keith Still, professor of crowd science at Manchester Metropolitan University.