The head of Iran’s Hajj and Pilgrimage Organization says at least 1,300 people have been killed in a crush during Hajj pilgrimage rituals outside Mecca.

Sa’eed Ohadi said on Thursday that at least 125 Iranian nationals were among those killed in the fatal stampede.

He added that the overall death toll is expected to exceed 1,500.

This as Saudi authorities say at least 717 people have been killed and nearly 863 others injured in the crush.

According to Saudi disaster officials, the incident occurred in Mina, near Mecca, at 9 am local time (0600 GMT) after two large masses of pilgrims coming down streets 204 and 223 fused together.

The incident took place as people were heading to participate in the symbolic stoning of Satan.

Over 220 ambulances and 4,000 rescue workers have reportedly been sent to the location.

“Work is underway to separate large groups of people and direct pilgrims to alternative routes,” the Saudi Civil Defense said.

During a meeting with senior officials responsible for the pilgrimage in Mina, Prince Mohammed bin Nayef, who heads the Saudi hajj committee, ordered an investigation into the deadly stampede.

Saudi blames pilgrims for tragedy

Saudi Arabia's health minister blamed the pilgrims for the deadly incident, saying the tragedy would not have happened if they "had followed instructions."

"Many pilgrims move without respecting the timetables" established by authorities, Khaled al-Falih said, adding that this is the "principal reason for this type of accident," El-Ekhbariya television reported.

"If the pilgrims had followed instructions, this type of accident could have been avoided," he said.

‘Saudi authorities responsible’

Hossein Amir-Abdollahian, Iran’s deputy foreign minister for Arab and African affairs, said the Iranian Embassy in Saudi Arabia, the Consulate and all other relevant organizations are actively working to determine the fate of the Iranian victims of the Thursday incident.

Amir-Abdollahian held the Saudi authorities responsible for the deadly incident, and said they should promptly act to manage the crisis.

“The imprudence on the part of relevant Saudi authorities to provide security for the pilgrims cannot be overlooked,” he said.

Amir-Abdollahian said the Saudi charge d'affaires has been summoned to the foreign ministry in Tehran over the fatal incident.

He added that a special commission has been set up by the Islamic Republic to follow up on the case of the Iranian pilgrims in Mina.

A file picture taken on October 4, 2014 shows Muslim pilgrims arriving to throw pebbles at pillars during the “Jamarat” ritual, the stoning of Satan, in Mina near the holy city of Mecca. (Photo by AFP)

Some two million people are currently in Mecca for this year’s Hajj pilgrimage.

Some 360 pilgrims lost their lives during the same ritual in Mina back in January 2006

This comes days after a massive construction crane collapsed into Mecca’s Grand Mosque, killing more than 100 people and leaving over 200 others wounded.

Muslim pilgrims walk past a crane that collapsed the day before at the Grand Mosque in Saudi Arabia’s holy Muslim city of Mecca, September 12, 2015. (Photo by AFP)

Separately, on September 21, a fire at a 15-story hotel in Mecca forced the evacuation of some 1,500 people. A fire also broke out at another hotel in the city days earlier, which left a number of foreigners injured.