Women in Syria face whippings and even execution under a harsh regime being enforced by Islamist rebels, it has been claimed.

Rebels from the Islamic State in Iraq and Sham (Isis) have imposed a harsh regime, flogging women who break a strict dress code, imposing a tax on Christians and banning any behaviour deemed immodest or sinful.

Isis drove Syrian rebels from the free Syrian Army and the Al-Nusra Front out of the city of Raqqa, in northern Syria about 99 miles east of Aleppo earlier this year, and began transforming what had been one of Syria's more liberal cities into a hardline Islamist mini-state modelled on its own version of Sharia law.

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One woman was allegedly sentenced to 20 lashes after an Isis "morality patrol" saw her holding hands with a male cousin. Another woman aged 19 was sentenced to 40 lashes after an Isis officer saw a picture of her on Facebook wearing a short-sleeved blouse, it has been claimed.

Everyone female aged 10 and over in Raqqa must cover themselves with the traditional abaya (the traditional cloak) and niqab (face covering), and Isis has decreed that no features should be displayed that are suggestive, vain or attention-seeking.

Women are also banned from talking loudly in the street, walking in public without a male chaperone (their father, brother or husband) and are not allowed to leave home after dark.

Everyone in the city has been banned from playing music in any public place and smoking, and the laws are reinforced by posters declaring that "a woman's modesty is her beauty" and by forcing men to go to the mosque and pray five times a day.

Churches have been burned and desecrated. Christians in the city have been banned from showing any sign or symbol of their religion and must pay a tax to remain in the city and avoid violent attacks.

Speaking who spoke secretly and anonymously to The Sunday Times, women in Raqqa spoke of living under the threat of violence and murder.

One woman said: "It's true that in Islam the veil is a must, but Islam doesn't impose the niqab."

Another said: "There have been whippings of women because of this. Some women have even been executed. It's become a case of living under the sword. Either one has to dress in the niqab by force of be executed."

According to a report by the World Economic Forum, the gender gap between men and women in Syria ranked 133rd of 136 countries in terms of opportunities like equal access to human rights like education and healthcare. Female healthy life expectancy is 65 and 11% of women marry between the ages of 15 and 19.