An unseasonable sandstorm has hit Lebanon and Syria, leaving at least 12 people dead and sending hundreds to hospitals for breathing difficulties.

At least three refugee women died in Lebanon on Tuesday where at least 750 others were hospitalised for asphyxiation or shortness of breath, the health ministry said.

The meteorological department at Beirut’s Rafik Hariri International Airport described the storm as being “unprecedented” in Lebanon’s modern history.

Visibility was significantly reduced and Beirut’s Traffic Management Centre advised drivers to be cautious in order to avoid accidents.

The National News Agency said the northern Lebanese district of Akkar was hit the hardest.

The storm also hit Jordan, Israel and Egypt. In Jordan, schools shut down or cut their days short.

In neighbouring Syria, the sandstorm affected the area of al-Mayadeen in the eastern province of Deir Ezzor on Monday. Hospitals there scrambled to attend to patients suffering from breathing problems.

The storm also reached the capital, Damascus, and the central city of Homs where one woman and five children reportedly died in al-Houla.

In Syria’s Hama, at least three women died, according to state media which also reported that 3,500 cases are being treated in several hospitals in various regime-controlled areas.

The pro-government Syrian Al-Watan newspaper says it forced the government to halt its air strikes against rebel fighters in the rebel-held areas in the north and centre of the country.

Activist Hadi al-Abdallah, in the northern province of Idlib, confirmed there were no strikes on the northern suburbs, which are usually bombarded on a daily basis.

“That’s the worst sandstorm I’ve ever seen. I couldn’t [see an] object just five metres away. Most people stayed indoors,” he told Al Jazeera.

Children wearing face masks play table football during a sandstorm in Homs [Reuters]