BEIRUT: Five civilians died on Monday in Russian air strikes backing Syrian regime forces as they chip away at the country´s last major rebel bastion, a war monitor said. The Syrian Observatory for Human Rights said the deadly raids hit the area of Jabal al-Zawiya in the south of the jihadist-dominated northwestern stronghold of Idlib. The Britain-based monitor says it determines who carried out an air strike according to flight patterns, as well as ammunition and aircraft involved. It said regime forces had rapidly gained ground in the southern part of Idlib in the past 24 hours. They have seized “several towns and villages” south of the M4 highway linking the coastal regime stronghold of Latakia to government-held second city Aleppo, it said. State news agency SANA said “units of the Syrian army continued to progress in the south of Idlib” province. Observatory chief Rami Abdel Rahman said the regime´s ultimate aim was to wrest back parts of the M4 still under control of the jihadists and allied rebels.