With no end to the Syrian crisis in sight, the body count keeps escalating. And civilians, along with terrorists, die in the line of fire as collateral damage.

Russia has killed 1,500 of these people through its airstrikes, which began on 30 September, says Syrian Observatory for Human Rights (SOHR), which reports on the war.

Among the deceased, 485 were civilians and the rest were militants belonging to the Islamic State (Isis) group or the al Qaeda-linked Nusra Front, SOHR has said.

An airstrike on Sunday by Russian jets killed at least another 30 people in a marketplace near the Turkish border town of Ariha in northwestern Syria.

Civil defence worker Mohamed Amine Qurabi, 25, describes the attack on Sunday: "The vendors were shouting loudly as people were buying and selling and suddenly we heard the sound of the planes and in less than a second the jets struck and there was deadly silence. I saw people thrown in the street, strewn corpses and terrified children crying and shouting for their parents."

SOHR confirmed 18 deaths and said the total is likely to be around 60.

Russia had been striking areas occupied by the rebels who are fighting against Syrian President Bashal al-Assad. But the strikes near the border towns intensified since Turkey downed a Russian warplane.

Turkey is believed to have sent arms and ammunitions across the border claiming it's humanitarian aid, reports Reuters.

A Syrian official, on condition of anonymity, was reported by IANS as saying that Russia conducts ground reconnaissance before areas are struck and it only focuses on areas which have been occupied by terrorists.

The Syrian Army has gained ground against the rebels since Russia started its airstrikes, he added.

The government official said the rebels besmirch Russia's anti-terror reputation by saying the country targets civilians.

Russia, which has been projecting its anti-terror campaign, has however not been distinguishing between Isis and rebels against Assad.

Civilians and rebels staying south of Aleppo, 50 km east of Ariha, where Turkish goods that sustain the rebel movement are believed to be sold, said Russian airstrikes have intensified in the towns close to the Turkish border.

Ground offensives were also carried out by the Syrian army, backed by Iranian and Hezbollah fighters, in Ariha, which was occupied by the rebels in May.