ISIS fighters march in formation (file)
ISIS fighters march in formation (file) Reuters

Syria's most extreme jihadist faction on Monday issued a ban on mannequins in shop displays and the sale of women's underwear to male customers, AFP reports.

The decision by the Islamic State of Iraq and the Levant (ISIS) in their northern stronghold of Raqa also bans men and women shopping together unless he is her husband, father or brother, the Syrian Observatory for Human Rights told the news agency.

The Observatory also said ISIS has decided that traditional garments on sale must be neither "tight, transparent or ornate."

Raqa is the only provincial capital in Syria to have fallen from the hands of President Bashar Al-Assad's regime, and it is now completely under the control of the Al-Qaeda inspired jihadist group.

ISIS is believed to be holding some 1,000 hostages in Raqa, rights groups say, many of them peaceful activists, rival rebels or civilians caught committing "crimes" such as heresy or smoking, according to AFP.

Since joining the civil war in Syria, many reports have surfaced regarding ISIS and its strict implementation of Muslim Sharia law in areas it captures.

ISIS has been accused of torturing and murdering prisoners, among them children and teenagers, and forcing Druze men to convert to Islam or die.

In one case, members of the group beheaded a person they said was a member of an Iraqi Shiite militia fighting for Assad, only to discover they had accidentally beheaded a fighter belonging to an allied rebel group.

In March, the group live-tweeted the amputation of a hand of a man charged with theft in the northern province of Aleppo.

The group also carries out frequent public executions, with some victims reportedly crucified in Raqa.

Similarly to ISIS, the Hamas regime in Gaza has also enforced a stringent interpretation of Islamic law in Gaza since violently taking power there in 2007.

Hamas ordered that mannequins shaped like women must be dressed in modest clothing, banned women and teenagers from smoking hookahs in public, ordered that women's clothing stores are not allowed to have dressing rooms, and declared that men cannot have hairdressing salons for women.

The group also introduced a strict dress code for female university students, demanding that they wear “modest clothing” and in March said it would introduce a penalty of lashes for certain criminal offenses.