Syrian government forces, Russia, bombard residential areas in suburbs of Idlib and Aleppo, activists and medics say.

At least eight civilians have been killed in government-led air raids in rebel-held towns on the outskirts of Syria‘s Aleppo province, as well as in villages across Idlib province – the last rebel-held stronghold in the country.

The air raids on Monday targeted several residential neighbourhoods in southern Idlib, Suleiman Abdulqader, a local activist, told Al Jazeera.

Four civilians – two women and two children – lost their lives in a raid that struck a village near Khan Sheikhoun, Abdulqader said.

Another two – a woman and a child – died in an attack in the village of Shnan, located in Ariha, south of Idlib.

Also on Monday, Russian warplanes targeted a medical facility in al-Zarbeh, a town in neighbouring Aleppo’s southern suburbs, killing at least two civilians, according to Syrian Civil Defence – also known as the White Helmets.

In the past 24 hours, government-led air raids have destroyed at least three hospitals, knocking them out of service, the Syrian Civil Defence said.

Attacks on hospitals and medical facilities in the past have preceded major government offensives on rebel-held areas, including the 2016 attack on the northern city of Aleppo and last year’s offensive on eastern suburbs of the capital, Damascus.

According to Abdulqader, who works with a network of activists across Idlib and its outskirts to document the frequency and aftermath of government-led raids, at least four other villages were targeted by Russian warplanes on Sunday – some for a second consecutive day.

Dozens killed

Syrian government forces, along with Russian military support, have intensified attacks on the region since April 26 in an attempt to drive out armed opposition groups and gain control over what once was a major commercial highway linking Syria to neighbouring Turkey and Jordan.

Opening the commercial and passenger routes through Idlib province would reassert the state’s control over an economy fragmented during eight years of conflict and now facing US and EU sanctions, economic experts say.

The latest fighting has killed dozens of people and displaced tens of thousands in Idlib and nearby rebel-held areas, who fled to safer regions further north.

It is the heaviest fighting in months, which has raised fears the government may launch a wider offensive to retake the country’s last major rebel bastion.

The United Nations has said the attacks have included the worst use of barrel bombs by the Syrian army in 15 months.

It says an estimated 323,000 people have been displaced in northwest Syria since September last year.

“The shelling and aerial strikes have increased in intensity and ferocity and the area hit has widened with more intensity,” Naji Mustafa of the Turkey-backed National Liberation Front (NLF) rebel group told Reuters news agency.

Idlib is held by an array of rebel groups, including Hay’et Tahrir al-Sham (HTS), a coalition of fighters including those formerly affiliated with al-Qaeda. The province is currently home to nearly three million people, half of whom are internally displaced.

Along with sharing a border with Turkey, Idlib is adjacent to Latakia province, a Syrian government stronghold that is home to the biggest military airbase of its major ally, Russia.

Last year, the Syrian government, backed in the war by Russia and Iran, was poised to mount a major offensive into parts of the northwest, including Idlib and adjoining parts of Hama and Aleppo provinces, raising concerns of a humanitarian catastrophe.

The attack was postponed after Russia struck a deal with Turkey that included the creation of a “demilitarised zone” in the region.