Muslim pilgrims and rescuers gather around people who were crushed by overcrowding in Mina, Saudi Arabia during the annual hajj pilgrimage on Thursday, Sept. 24, 2015. Hundreds were killed and injured, Saudi authorities said. (AP Photo)

The death toll is still climbing after a horrifying stampede in the environs of Mecca, site of the annual hajj, the holiest pilgrimage in Islam. More than 700 pilgrims were crushed to death in Mina, a bowl-shaped desert plain that becomes a vast and crammed temporary encampment during the hajj.

It's also the site of an important hajj ritual, as my colleagues explain:

Crowds were making their way from a vast settlement of more than 160,000 tents to perform a hajj ritual to commemorate the stoning of the devil by the prophet Abraham, known in Arabic as Ibrahim.

During the ceremony, pilgrims fling pebbles at one of three pillars representing the devil. The rite is considered one of the most dangerous parts of the pilgrimage because of the large crowds it draws through the Mina area’s narrow roads.

“I thought I was going to die,” 56-year-old Radhi Hassan, a pilgrim from Iraq who was caught in the crush, said by phone. “I pushed people and was able to drag myself out.”

Saudi authorities have opened an investigation into what prompted the tragic incident, one of the worst disasters to befall the pilgrimage in recent decades. It follows a fatal mishap two weeks ago when a crane near the main mosque at Mecca collapsed, killing more than 100 people.

In the aftermath of the tragedy, attention has centered on the ballooning size and scale of the pilgrimage. From a gathering of some 30,000 people in the 1930s, it drew 3 million in 2012. The Saudis have attempted to keep pace with the influx, spending billions on infrastructure at the country's holy areas. But the risks remain, and the blame game has just begun.

Prince Khaled al-Faisal, head of Saudi Arabia's Central Hajj Committee, appeared to point the finger at "some pilgrims with African nationalities."

Meanwhile, Iranian officials have used the occasion to loudly chastise Saudi Arabia -- the two countries are long-standing rivals and are locked in proxy struggles across the region. Dozens of Iranians -- one official claimed more than 100 -- were believed to be among the casualties.

"Today's incident shows mismanagement and lack of serious attention to the safety of pilgrims," said Said Ohadi, head of Iran's hajj organization. "There is no other explanation. The Saudi officials should be held accountable."

Iranian state media singled out the nearby presence of the Saudi crown prince as a potential reason for the overcrowding and stampede.

And the country's supreme leader, Ayatollah Ali Khamenei, tweeted criticism of his Saudi counterparts.

The enmity between the two countries is shaped by sectarian divisions --  Iran is a Shiite theocratic state; the kingdom espouses a staunchly puritanical brand of Sunnism. In 1987, clashes between Shiite pilgrims and Saudi security forces in Mecca led to hundreds of deaths, including some 275 Iranian pilgrims.

As part of the ceaseless rhetorical war between the two countries, a prominent Iranian cleric earlier this year called for the holy sites at Mecca and Medina to be "emancipated" from "the servitude and the looting of the Saudi regime."

Ayatollah Javadi Amoli also lambasted the Saudi intervention in Yemen and attacked the kingdom's ruling House of Saud. "The current Saudi custodians however are the [descendants] of those who turned it to a house of idols and indulged themselves in drunken revelry," said Amoli, as quoted by the semiofficial Mehr News Agency. "Those were the grand-grand fathers of the current custodians, whom lost in gambling the custodianship or traded it for few wineskins."

The custodianship of the two mosques at Mecca and Medina grants a great deal of political legitimacy and regional influence to the Saudi royals. But, in the long history of Islam, the sites of the hajj have only recently been under their guardianship. For centuries, the Ottoman Empire held sway, a fact that the mayor of Ankara invoked when he tweeted on Thursday that the responsibility for Mecca should be turned over to Turkey.

Mega construction projects undertaken by the Saudis in the holy cities have angered many elsewhere in the Muslim world. Some of them have led to the destruction of ancient shrines and tombs, draining Mecca of its "history and religious and cultural plurality," as one commentator put it.

After the crane accident earlier this month, a leading Egyptian cleric suggested that administration of the sites be handled by a collective grouping of Muslim states.

"Many mistakes have been made during the hajj ceremony in recent decades," said Sheikh Salman Mohammad, an adviser to Egypt's Ministry of the Endowment. "The bloody Friday incident was not the first case and will not be the last, either." He was grimly prescient.