Baghdad, Iraq: Torrential rain caused chaos across several parts of Iraq on Thursday, with the water causing thigh-high flooding on some Baghdad streets and damaging camps for the displaced.

The storm that hit Baghdad on Wednesday evening was unusually violent and the first after a long, dry summer.

The poor condition of infrastructure in Baghdad, the Arab world's second largest city with an estimated population of more than eight million, resulted in spectacular flooding.

Social media was awash with pictures and footage of the devastation, that left many people unable to reach their workplace and led the government to declare Thursday a holiday.

In one video, the staff in a Baghdad hospital could be seen wading knee-deep in water, in another cars were shown drifting away with the current on flooded streets.

Residents of some Baghdad neighbourhoods spent most of the night bailing rain mixed with sewage water from the ground floor of their homes.

"Forget the furniture, I am afraid of the diseases this can spread. Shame on our past leaders, who allowed everything in this city to rot," said Ahmed, from northwestern Baghdad.

A wave of protests erupted this year in Iraq over the poor quality of services, including the lack of electricity when summer temperatures topped 50 degrees Celsius (120 Fahrenheit).

In areas around the capital, rivers of mud wrecked the tented camps set up for the people displaced by conflict in the western province of Anbar and other regions of Iraq.

The governor of Anbar, a vast province west of Baghdad where much of the latest fighting between government forces and the Islamic State group has focused, urged the authorities to help.

Several camps for internally displaced people in Anbar were badly affected by the downpour and governor Suhaib al-Rawi said the bridge leading to safer provinces should be opened.

Weather forecasts predicted more thunderstorms for Friday and next week.