Although Saudi Arabia has been enlarging the space in Mina where pilgrims gather for the stone throwing ritual during Haj, Thursday's horrific loss of life proves that more needs to be done. This in essence is what Custodian of the Two Holy Mosques King Salman said in a statement, ordering a review of the Kingdom's Haj plans and entire procedures for the annual Haj following the stampede in Mina which left at least 717 people dead and over 800 injured. Apparently, the disaster began when one wave of pilgrims heading for the Jamarat found themselves heading into a mass of people going in another direction. It became chaotic and suddenly people started falling over each other. The Health Ministry said the crush occurred because many pilgrims moved "without respecting the timetables" established by authorities and that if they had followed instructions, the accident could have been avoided. The high temperatures -- 46 degrees Celsius -- and fatigue of pilgrims after having attended Arafat might have been contributing factors. Officials deployed 4,000 workers, along with 220 ambulances and other vehicles to Mina in response to the disaster. Unfortunately, incidents like this can happen in an instant. And it takes only a few minutes before a crush becomes a calamity. It's not just that there were tens of thousands of people at the intersection of Street 204 and Street 223 in Mina; it's also being in the same place at the same time in order to complete their rituals. This makes the Jamarat possibly the most difficult part of the Haj. As such, in 2009, the government completed a five-story bridge where pilgrims could toss the stones. The idea was to allow for more room. In general, the authorities have spent billions of riyals on improving transport and other infrastructure to try to prevent such incidents. This year they deployed 100,000 security personnel and 25,000 extra health workers to oversee crowd management and ensure pilgrims' safety during the pilgrimage, as well as 100,000 air-conditioned tents for temporary accommodation. Officials used surveillance cameras and other equipment to limit the number of people converging on the site, and the Jamarat Bridge has multiple exits to facilitate the flow of people. All this is because the Haj is possibly the largest gathering of human beings in the world. As a consequence, it poses an immense logistical and security challenge for the Kingdom, given the sheer number of people who come from all over the world, and whom in so many cases have saved for years for this once-in-a-lifetime opportunity to make the Haj. Keeping them safe is a formidable task. Official figures said 1,952,817 pilgrims performed this year's Haj, including almost 1.4 million foreigners. Managing such crowds in a small venue like Mina and at the Jamarat is extremely difficult. King Salman has directed the agencies concerned to carry out a prompt investigation into the circumstances that led to the Mina tragedy, and present him with report at the earliest. In expressing his condolences, King Salman instructed the agencies concerned to “improve the standard of the organization and management of the movement of pilgrims” to try to alleviate the pressure posed by masses of pilgrims converging on the site of the stoning ritual. What is needed is an all-around review of crowd control. The authorities must take a closer look at what needs to be done – the police, extra measures, the technology – to try to find ways to prevent such catastrophes.