The Russian Defence Ministry on Tuesday claimed that at least 20 civilians were killed in a B-52 bomber strike carried out by the US on the Idlib province in Syria on January 3.

"As we remember, on September 29 last year, the US aviation carried out an attack in the Deir-ez-Zor targeting government forces. After this attack, the Islamic State started its advance," Russian Chief of General Staff Valery Gerasimov said during a Defence Ministry meeting, as cited by RIA Novosti news agency.

"The latest example of this is the January 3 airstrike, when a B-52 bomber -- without warning the Russian side -- hit a target in the town of Sarmada, Idlib Province, which is covered by the cessation of hostilities agreement. Over 20 civilians died as a result of the airstrike." -IANS