Syrian regime forces entered a key northwestern town on Sunday amid intense fighting with Islamist militants and their rebel allies which has left dozens of combatants dead, a war monitor said. The Syrian Observatory for Human Rights reported “fierce clashes” as it said regime ground troops penetrated Khan Sheikhoun in Idlib province for the first time since they lost control of it in 2014. The latest fighting, which broke out overnight Saturday to Sunday, has already killed at least 59 extremists and allied rebels as well as 28 members of pro-regime forces, the Britain-based monitor said. Pro-regime forces have been advancing over the past few days in a bid to encircle Khan Sheikhoun from the north and west and to seize a key highway. The road runs through Idlib, connecting government-held Damascus with the northern city of Aleppo, which the regime retook from rebels in December 2016 after a pulverising Russian-backed offensive. On Sunday they retook the village of Tel Al Nar and nearby farmland north-west of Khan Sheikhoun before closing in on the town, the Observatory head Rami Abdel Rahman said. They then advanced into the northwestern districts of the town amid “ferocious resistance” from Islamist militants and allied rebels, he said. Hayat Tahrir Al Sham, led by Syria’s former Al Qaeda affiliate, carried out several suicide bombings to slow the advance of regime troops, Mr Abdel Rahman said. HTS controls most of Idlib province as well as parts of the neighbouring provinces of Hama, Aleppo and Latakia. A buffer zone deal brokered by Russia and Turkey last year was supposed to protect the Idlib region’s three million inhabitants from an all-out regime offensive, but it was never fully implemented. Regime and Russian air strikes and shelling since late April have killed more than 860 civilians, said the Observatory, which relies on sources inside Syria for its information. On Sunday, air strikes by the Syrian regime and its ally Russia killed two people, including a child, in the south of Idlib, the Observatory said. More than 1,400 insurgents and at least 1,200 pro-regime forces have been killed since April, the monitor said. The violence has displaced more than 400,000 people, the United Nations said. Khan Sheikhoun was hit by a chemical attack that killed more than 80 people in April 2017, <a href="https://www.thenational.ae/world/syrian-government-the-likely-culprit-of-khan-sheikhoun-chemical-attack-1.71291">attributed to the Syrian regime</a> by the UN and international experts. In response, US President Donald Trump ordered strikes on the regime’s critical Shayrat airbase. Now almost emptied of inhabitants, Khan Sheikhoun sheltered almost 100,000 people before the start of the current military escalation, the majority displaced from Hama province. “Many of these people have been displaced up to five times,” the UN’s regional spokesman for the Syria crisis, David Swanson, told AFP on Saturday. “Ongoing clashes, shelling and air strikes, including the use of barrel bombs, continue unabated” and have damaged schools and hospitals, he said. Syria’s conflict has killed more than 370,000 people and displaced millions at home and abroad since starting with the brutal repression of anti-regime protests in 2011.