According to the Syrian Observatory for Human Rights, the attacks occurred early Monday on the north-western outskirts of the city of Idlib.
ADVERTISEMENTAt least eight anti-regime fighters were killed by Russian air strikes on the last major rebel stronghold in northwest Syria.
According to the NGO the Syrian Observatory for Human Rights (SOHR), "Russian warplanes carried out airstrikes on the western outskirts of the city of Idlib, targeting a Hayat Tahrir al-Sham (HTS) military base".
"At least eight fighters" from this jihadist group were killed, added Rami Abdel Rahmane, director of the UK-based SOHR, which has an extensive network of sources in Syria.
Several other fighters were wounded, according to the NGO.
An AFP correspondent in Idlib said the strikes had targeted an agricultural area in the region, the last major rebel stronghold in north-west Syria, partly controlled by the jihadist group HTS.
HTS fighters deployed around the targets and barred journalists from entering.
Russia is the main supporter of President Bashar al-Assad's regime and has been intervening militarily in Syria since 2015.
Hayat Tahrir al-Sham, which stems from the former local branch of al-Qaeda, is the main group active in these territories, where other less influential rebel factions are also present, supported to varying degrees by Turkey.
With the support of Russia and Iran, the Syrian regime has recaptured most of the territory lost at the start of the war, which began in 2011 with the repression of pro-democracy demonstrations.
The Idlib region is subject to a ceasefire negotiated by Russia and Turkey after a regime offensive in March 2020.
Despite repeated violations, the ceasefire is generally being respected.
The war in Syria, which began in 2011 with the repression of pro-democracy demonstrations, has claimed more than half a million lives and displaced around 13 million people.