Bombs planted on a military bus have killed 14 Syrian soldiers in the centre of Damascus, state media reported, denting the regime's claims of having secured the capital. Hours later on Wednesday in north-western Syria, artillery shelling by forces loyal to President Bashar Al Assad killed 13 people in a town under Turkey’s sphere of influence, monitoring groups said. The attack on the town of Ariha in Idlib governorate during school drop-off time resulted in the heaviest reported civilian death toll in one day since a proxy war between Russia and Turkey in the region renewed last month. The two countries were on the verge of war over Idlib in February and March 2020, in a culmination of the internationalisation of the Syrian civil war, before Moscow and Ankara pulled back from the brink. Russia's intervention in Syria in 2015 enabled the regime to overrun rebel areas in Damascus and its surrounding area. Russian firepower restored other cities and rural areas, mostly along an axis running north and south of Damascus, to the regime. But Russian might has not been able to end the civil war, with Moscow becoming the main actor on the diplomatic arena regarding the situation as US attention turned elsewhere. The civil war broke out after the regime cracked down on the revolt in March 2011 against five decades of Assad family rule over Syria. The majority Sunni country has been dominated by members of its Alawite minority since mostly Alawite officers, among them Assad's father Hafez, took power in the 1963 coup. The official Syrian news agency quoted a military source as saying that the two bombs went off at 6.45am while the military bus was near a main intersection during the morning rush hour in Damascus. The bombs were "attached to the bus" before it neared the Hafez Al Assad Bridge, a main flyover in the centre of the city, the source said. A third device was dismantled on site where it fell off after the explosion. The site is a few hundred metres away from the agency's offices, the Interior Ministry and the Four Season Hotel, one of the most expensive hotels in Damascus, where UN staff stay. “We will chase these terrorists who committed this heinous crime wherever they are,” Interior Minister Mohammad Khaled Al Rahmoun said while inspecting the explosion site. He said an investigation would be launched. Pictures on state television, which described the blast as “terrorist bomb attack", showed the charred bus as medics were trying to remove bodies. Loyalists forces and militias supported by Iran have been pushing troops and personnel from Damascus and other areas to the north-west for the last two months before an expected attack on Idlib, Syrian opposition figures in Amman and Istanbul say. The shelling that reportedly killed 13 people in Idlib on Wednesday was aimed at the town of Ariha. The governorate is home to the largest concentration of refugees in Syria. They number around three million, with another one million in areas controlled by Turkey in the neighbouring province of Aleppo. The Syrian Civil Defence, also known as the White Helmets, said one of the victims was an 8-year-old girl called Rimas who was holding her father's hand when the attack took place, killing them both. Two White Helmet volunteers lost a family member during the shelling. Basil Hafez, whose sister Qamar Hafez, an Arabic teacher, was killed along with Muhammad Al Amin who lost his 14 year-old brother, Ibrahim. Ariha lies on the M4, a major motorway patrolled by the Turkish Army. The M4 links the city of Aleppo to the Mediterranean coast, where the bulk of Russian forces in Syria are based. Attacks by the regime and pro-Iranian militia in recent weeks, as well a Russian air bombing, were all thought to be with the aim of capturing the road. The Idlib Media Group, run by citizen journalists opposed to Assad, said the shelling started at 7.55am on the town’s square and main market. Three schools are located in the vicinity. “Most of those who died were on their way to the school,” the group said. Three children and one female teacher among the dead have been identified, it said. Rami Al Sayyed, an opposition activist in Idlib, said the attack was a continuation of heavy targeting of frontline regions in recent weeks. “We have seen the regime and its allies using field artillery and rocket launchers as a prelude to advancing on the ground,” he said by phone. A Syrian opposition source in Amman said that at least three small Turkish bases around Ariha escaped the shelling. Turkey has more than a dozen fortifications and observation posts along the M4. These are part of a military ring separating the Turkish sphere of influence in Idlib and Aleppo from regime areas. In February 2020, a dispute between Ankara and Moscow almost led to war in north-western Syria, after an air strike in Idlib killed 34 Turkish soldiers. Turkey retaliated by killing dozens of regime personnel in artillery and drone attacks, and destroying a significant portion of its heavy armour in Idlib, before a deal between Ankara and Moscow in March 2020. Hostilities eased after the pact but low-intensity warfare in the north-west continued. Among its participants is Russian-backed Kurdish People Protection Units (YPG) militia based in the pocket of Tal Rifaat north of the city of Aleppo, adding another layer of complexity to the conflict. The deal in March 2020 gave the advantage at the front lines in north-west Syria to the regime and its militia allies. Officials in Ankara say Turkey cannot afford to cede any more territory in Idlib, citing the possibility of refugees reaching the Turkish border if the regime and its allies push further into the region. Idlib residents say the Turkish military has been sending reinforcements to the region since last month and setting up more small bases in the governorate. But speculation has been mounting among members of the Syrian opposition to Assad that Turkey would swap areas in Idlib near the M4 for Tel Rifaat with the Russians, and possibly other areas captured in the last decade by Kurdish militia to the north-east. With the civil war having tilted in favour of the regime, attacks in the Syrian capital have been rare in the past three years. Rami Abdul Rahman, head of the Syrian Observatory for Human Rights, a war monitor based in Britain, said the bus bombing on Monday constitutes "a huge security breach". “Whoever did this – whether it's ISIS or Al Nusra militant group or others – wanted to send a message to the regime that there is no safe place,” he said.