At least 17 fighters allied to the Syrian regime were killed on Thursday in surprise ISIS attacks in southern Syria, said the Syrian Observatory for Human Rights. Six Syrian regime troops, nine Iranians and fighters belonging to pro-Iran militias were among the casualties in the assaults that took placed in in the desert of the southern province of Sweida. Nine ISIS members were also killed in the violence. They were the first attacks of their kind in the area, where no ISIS presence had been noted in more than a year, Observatory director Rami Abdel Rahman said, according to Agence France Presse. ISIS has ramped up its attacks against pro-regime forces since its fighters last month left their last stronghold near Damascus under an evacuation deal with the regime. The new toll brings to 179 the number of pro-regime troops killed in more than two weeks in extremist attacks across the country since May 22. At least 89 terrorists were killed during that same period. ISIS in 2014 proclaimed a so-called "caliphate" in Syria and neighboring Iraq, but has since lost most of that territory to separate offensives by Russia-backed regime troops and a US-backed Kurdish-Arab alliance. The extremists now control no more than three percent of Syria, the Observatory says, mostly in the eastern desert near the border with Iraq. Iraq has recently been carrying out air strikes against ISIS pockets in Syria. Earlier this week, ISIS assaults in the eastern province of Deir Ezzor killed 45 pro-regime fighters. More than 350,000 people have been killed since Syrias conflict started in 2011 with the brutal repression of anti-regime protests.