At least 22 persons were killed on Wednesday in Russian airstrikes against a school in Syria, a monitor group said.Among the dead were 14 children, all students from the school, and one teacher in the Idlib province, Efe news quoted the official from Syrian Observatory for Human Rights as saying.According to the monitoring group, Russian air force carried out at least six airstrikes against the school and its surroundings.In the same region, Syrian army helicopters launched explosive barrels on the town of Khan Shaykhun, which were followed by air force bombings. However, no casualties were reported.The region of Idlib is almost completely under the control of Islamist and rebel groups, primarily Jabhat Fateh al-Sham, which until its recent rebranding was the al-Qaeda-linked Jabhat al-Nusra.