Cairo, Aug 15 (IANS/EFE): The Islamic State (IS) Sunni extremist group has banned the study of philosophy and chemistry in schools in the northern Syrian city of al-Raqa and established an "Islamic curriculum" for students, the Syrian Observatory for Human Rights (SOHR) said Friday.

The IS had asked teachers and school directors to "prepare an Islamic education system in the schools of al-Raqa", which would be reviewed by the board of education, formed by the IS itself.

The "Islamic experts" belonging to the IS decided to exclude chemistry and philosophy from the educational programme because "they do not fit in with the laws of god", the SOHR reported.

The IS promised adequate wages to teachers and principals after the government of Syrian President Bashar al-Assad stopped paying their salaries following the takeover of al-Raqa by Islamist rebels.

IS radicals closed several schools in the province which had an educational programme consistent with the Syrian regime or with rival Islamic brigades which controled al-Raqa before them.

The jihadis Thursday slaughtered nine members of rival Islamic groups in the Syrian town of Akhtarin in northern Aleppo province.

They also stoned to death one of their militants, a Tunisian, after he raped a young displaced girl from Deir al-Zur city.

The IS, formerly known as the Islamic State of Iraq and Greater Syria (ISIS), controls al-Raqa and large parts of Deir al-Zur, where various armed groups have sworn allegiance to the radical organization.

The jihadis last June established an “Islamic caliphate” in the territories under their control in Syria and Iraq.