BEIRUT: Regime airstrikes have killed 33 civilians in the past 24 hours in Syria’s northwestern province of Idlib where government forces are fighting terrorists, a monitor said on Monday.

On Monday alone, the strikes killed 16 civilians including 11 in a vegetable market in the town of Saraqeb, the Britain-based Syrian Observatory for Human Rights said.

The 17 others were killed on Sunday in raids on various areas of the province, large parts of which are controlled by Hayat Tahrir Al-Sham (HTS), which is dominated by Al-Qaeda’s former Syria affiliate.

“Regime war planes have intensified their strikes over the past 24 hours after relative calm due to bad weather,” Observatory chief Rami Abdul Rahman said.

Syrian troops had been advancing on Idlib as part of a fierce offensive launched in late December with Russian backing.

At the market in Saraqeb, an AFP correspondent saw pools of blood on the ground. Small trucks loaded with sacks of potatoes stood abandoned after their windows were blasted from their frames.

In front of a hospital in the town, a motorbike and a car were trapped below the rubble and twisted metal.

An alliance of jihadists and rebels overran the vast majority of Idlib province in 2015.

On Jan. 21, Syria’s army said it had captured the vital military airport of Abu Duhur on the edge of Idlib province, in a breakthrough for the government in the last Syrian province beyond its control.

With the airport’s capture, the army said, troops would secure a key route leading from the neighboring province of Aleppo south to Damascus.

Meanwhile, delegates on Monday arrived for the first Syria peace congress in Russia, but expectations for the dialogue were tempered after the country’s main opposition group said it would boycott the event.

The opposition has accused the regime and its Russian backers of continuing to rely on military might — and showing no willingness to enter into honest negotiations.

Moscow has invited 1,600 people to the talks in the Black Sea resort of Sochi as part of a broader push to consolidate its influence in the region and start hammering out a path to a political solution to end the bloody conflict.

Only a fraction of the invitees are set to participate in the event, however, according to a list of participants seen by AFP which has about 350 people on it.

The aim of the Tuesday congress is to bring Syria closer to creating a post-war constitution, after two days of separate UN-backed talks in Vienna last week closed without any sign the warring sides had met face-to-face to discuss the groundwork for the document.

The Kremlin has downplayed expectations of the event, with presidential spokesman Dmitry Peskov telling journalists on Monday that “breakthroughs in the task of political regulation in Syria are hardly possible.”

He added however that under-representation will not “disrupt this congress or undermine its importance,” calling the Sochi talks a “very important” step toward peace.