Iraqi Shia holy city of Karbala mourns stampede deaths

Nassif al-Khattabi declared a three-day mourning period, as nine of the dozens injured remained a critical condition in hospital. 

Iraqi Prime Minister Adel Abdul-Mahdi also arrived at the city on Wednesday and visited some of the injured in hospital.

Tuesday's incident was Iraq's deadliest mass stampede in recent history during Ashura, whose commemorative marches were previously targeted by Sunni extremist groups.

Hundreds of thousands of Shia pilgrims from around the world swarmed Karbala, around 100 kilometres (60 miles) south of Iraq's capital Baghdad, to commemorate the death of the Prophet Muhammad's grandson, Hussein.

The packed processions of black-clad worshippers made their way to his gold-domed shrine, carrying flags and crying out, "We sacrifice ourselves for you, Oh Hussein!"

As the massive crowds pressed forward, a stampede broke out that left at least 31 people dead and more than 100 more wounded, according to Iraq's health ministry. 

Ministry spokesman Saif al-Badr said the death toll could rise as nine of the wounded remained in critical condition.

Iraq is majority Shia, but under ex-dictator Saddam Hussein's regime, the vast majority of Ashura commemorations were banned.

Now the day is a national holiday, and devout Shia pilgrims travel from neighbouring Iran and Gulf countries, as well as Pakistan and India, to mark it in Iraq.

Streets across the country were shuttered on Tuesday to allow for funeral-style processions and elaborate re-enactments of the Battle of Karbala. 

Similar ceremonies took place in Baghdad, in the southern city of Basra and in Iraq's second holy city Najaf, where the Prophet Muhammad's son-in-law Ali is buried.

After Saddam's ouster in 2003 by the US-led invasion, Iraq was rocked by years of sectarian violence, which made such processions deadly.

In 2005, at least 965 pilgrims heading to the Imam Kadhim shrine in Baghdad during a different holiday died after rumours of a suicide bomber in the crowd sparked a mass stampede.

And in 2013, nearly 40 Shia pilgrims were killed across various Iraq cities in a series of attacks on Ashura. 

The following year, the Islamic State group swept across a third of Iraq and carried out mass attacks against civilian populations, including Shias. 

Iraq declared victory against IS nearly two years ago, but the group still carries out hit-and-run attacks in remote parts of the country.

Agencies contributed to this report.

Follow us on Twitter: @The_NewArab