Updated

Islamic State (ISIS) fighters ambushed a city and several villages in southern Syria on Wednesday, triggering ferocious clashes between residents and the militants that provincial health officials said killed more than 200 people.

The coordinated attacks across the province of Sweida, which included several suicide bombings, shattered the calm of a region that has been largely insulated from the worst of the violence of Syria's seven year long civil war.

The suicide bomb blasts inside the provincial capital, also called Sweida, were apparently timed to coincide with attacks on villages in the eastern countryside, creating mayhem across the province.

The attacks triggered deadly clashes between pro-government fighters and residents who picked up weapons to defend their hometowns on one side and ISIS militants on the other.

By nightfall, the province's health directorate had recorded 204 civilians killed and 180 wounded, according to local official Hassan Omar, making it the single bloodiest day for the province since the 2011 national revolt that sparked the ongoing civil war.

Sultan Bou Ammar, a resident of the village of Shbiki, said some residents unwittingly opened their doors when militants knocked early Thursday morning, so unexpected was the attack.

"They kidnapped more than 40 people, all of them women or children," said Bou Ammar.

The Syrian Observatory for Human Rights monitoring group said at least 183 people were killed, including 94 residents who were part of local defense militias that have the backing of the Syrian government. At least 45 ISIS militants were killed in the fighting.

Al-Ikhbariya state-run TV showed images from several locations in the province and its capital where the bombers blew themselves up.

The rare attacks in Sweida, populated mainly by Syria's minority Druze, came amid a government offensive elsewhere in the country's south. Government forces are battling the ISIS-linked group near the frontier with Israeli-occupied Golan Heights and near the border with Jordan. The group also has a small presence on the eastern edge of Sweida province.

Since their offensive in June, Syrian President Bashar Assad's forces have retaken territories controlled by the rebels along the Golan Heights frontier and are now fighting militants in the country's southern tip.

ISIS has been largely defeated in Syria and Iraq, but still has pockets of territory it controls in eastern and southern Syria.

The extremist group boasted that its "soldiers" killed more than 100 people in Sweida. In a statement posted on the group's social media channels, it said its militants carried out surprise attacks on government and security centers, sparking clashes with Syrian troops and allied militias.

The death toll in Sweida, initially reported at 27, quickly climbed. The Observatory also reported a series of suicide blasts and the clashes in the province's countryside. It said the dead included civilians, pro-government fighters and ISIS militants.

An activist-operated media platform on Facebook, Sweida News Network said a local militia was fighting the advancing ISIS-affiliated group and that at least 30 militiamen were killed in the clashes with the militants.

Al-Ikhbariya said one of the suicide bombers hit a vegetable market in the city of Sweida just after 5 a.m., a busy time for the merchants at the start of their day.

The bomber drove through the market on a motorcycle and there detonated his explosives, the TV station said. A second attacker hit in another busy square in the city. Two other attackers blew themselves up as they were chased by security forces, the TV said.

The city of Sweida has largely been spared most of the violence that Syrian cities have witnessed in the years since the conflict started in 2011. The provinces' religious and civil leaders have preached coexistence with Damascus, even as cities elsewhere in the country heaved with protests.

But the largely rural province has suffered from emigration as weak employment prospects and conscription pressures to serve in the national army have pushed men out.

Bou Ammar, from Shbiki, said there weren't many men left to defend the village when the militants attacked.

"We got reinforcements from (security) forces near and far, God grant them peace," he said.

For the southern offensive, government forces redeployed troops from Sweida province last month to attack rebels and ISIS-affiliate militants in the nearby provinces of Daraa and Quneitra.

The government is now in control of Daraa but continues to battle the ISIS-affiliate militants in Quneitra.