Russian warplanes fired missiles at a training camp run by a US-backed rebel group in the northwestern Syrian province of Idlib  Thursday, the group's spokesman told AFP.

"At exactly 10:30 am (0730 GMT), Russian planes targeted Suqur al-Jabal's training camp, with four Russian planes firing more than 10 missiles," said Mustafa Halabi, spokesman for Suqur al-Jabal (Falcons of the Mountain).

He said two more Russian warplanes attacked the base at noon, but that no rebels were hit.

Rebels from the group have received training and equipment as part of a $500-million US programme to build up a force to combat the Islamic State group in Syria.

But the Pentagon programme, which had originally aimed to train around 5,400 vetted fighters a year for three years, has come under fire.

In September, US General Lloyd Austin told the Senate Armed Services committee only "four or five" US-trained rebels were on the ground fighting in Syria.

But later in September, more than 75 newly trained rebels were deployed to northern Syria and assigned to either Suqur al-Jabal or Division 30, another opposition unit.

Russia began conducting air strikes in Syria Wednesday, and has insisted that it is only targeting the Islamic State group and other "terrorist" factions.

But US and French officials have expressed doubt, saying they had indications Russian warplanes were targeting groups opposed to Syrian President Bashar al-Assad instead of jihadists.

Source: AFP