A string of suicide blasts and raids claimed by the Islamic State group killed more than 180 people in southern Syria on Wednesday, in one of the jihadists' deadliest ever assaults in the country. The Syrian Observatory for Human Rights said the attacks hit several areas of the largely government-held southern province of Sweida, where IS retains a presence in a northeastern desert region.
They came almost a week into a deadly Russia-backed regime campaign to oust IS fighters from a holdout in a neighbouring province of the country's south.
IS claimed responsibility for the violence, saying "soldiers of the caliphate" attacked Syrian government positions and security outposts in Sweida city, then detonated explosive belts.
The Britain-based Observatory said four suicide bombers targeted Sweida city while others hit small villages to the north and east and shot residents in their homes. At least 183 people were killed, including 89 civilians, the Observatory said. The remaining 94 dead were pro-regime fighters, mostly residents who picked up arms to defend their homes, it said.
Sweida, whose residents are mostly from the Druze minority, has been relatively insulated from the war that has ravaged the rest of the country since 2011.
"It's the bloodiest death toll in Sweida province since the start of the war" and one of the deadliest ever IS attacks in Syria, Observatory head Rami Abdel Rahman said.
He said regime forces eventually ousted IS from several villages its fighters had seized and put an end to the attacks.
"Some residents who fled the attacks on their villages are returning and finding people dead in their homes," Abdel Rahman said. At least 38 IS fighters were also killed, including the suicide attackers.
State media confirmed the attacks had killed and wounded people in Sweida city and villages to the north and east but did not give a specific toll.
Omar, a resident of Sweida city, told AFP explosions began rocking the city around 5:30 am local time (0230 GMT). "The blast was sudden and unexpected. Never in its history has Sweida seen such a tough day," he told AFP. State news agency SANA published images from the city of the attack's aftermath, showing a victim's remains sprawled on a staircase near a damaged wall. Abandoned shoes lay in the middle of the road among fruit that had spilled out of cartons.
The UN's humanitarian coordinator in Syria Ali al-Zaatari condemned the "terrorist bombing in Sweida city," saying all civilians should be protected. Government ally Russia said the IS attacks "confirm the need for energetic and coordinated efforts by the international community to eradicate this universal evil from Syrian territory." Pro-government forces ousted IS from urban centres in eastern Syria last year, but surprise IS raids in recent months have killed dozens of regime and allied fighters.
The jihadists still hold some territory in Syria's south, including in Sweida and another isolated but larger patch in neighbouring Daraa province, to the west.
That pocket is held by Jaish Khaled bin al-Walid, a jihadist faction whose 1,000 fighters have pledged allegiance to IS.
After ousting mainstream rebels from most of the south, President Bashar al-Assad's troops and his Russian allies are now closing in on the IS pocket in Daraa.
SANA said the attacks on Sweida were an attempt to relieve pressure "on IS remnants facing their inevitable end in the western Daraa countryside."
On Wednesday, Russia-backed regime forces pressed their heavy bombardment of IS territory in Daraa.
At least 41 civilians have been killed in air strikes on the jihadist holdout since July 19, while clashes have killed 49 regime fighters and 67 jihadists, says the Observatory.
Syria's south is ostensibly protected from fighting by a ceasefire brokered by world powers last year, but violence has risen dramatically in recent weeks.
Last month, Assad's forces launched a lightning assault that battered rebel areas in the south and brought most of Daraa province under his control. They then moved on to Quneitra, the neighbouring province which borders the Israeli-annexed Golan Heights. On Tuesday, a Syrian military source accused Israel of firing at one of its warplanes as it carried out operations against jihadists in Quneitra.
Israel's army earlier said it had shot down a Syrian fighter jet that had infiltrated Israeli airspace, risking another escalation around the sensitive buffer zone.
The Damascus regime has long accused Israel of backing IS, which overran large parts of Syria and neighbouring Iraq in 2014 but has since lost most of that territory. More than 350,000 people have been killed and millions displaced since Syria's war started in 2011 with the brutal repression of anti-government protests.