Syrian rebels may have used surface-to-air missiles to bring down a government helicopter this week, a development that could alter the balance of power in the country’s north.

Footage posted online appeared to show a shoulder-fired missile being used to down a Mi-17 military helicopter in Idlib on Tuesday, amid heavy fighting between rebels and Russian-backed government forces.

A group of Syrian rebel fighters is seen celebrating the downing of the aircraft, but it is unclear who fired the missile and the video could not be independently verified.

The Turkish military is currently on the ground in the province and it is possible its troops may have handled the weapon on behalf of rebel groups it supports.

If confirmed, the use or supply of the missiles to target Syrian government aircraft would mark a further escalation in the multifaceted war. The successful use of such weaponry may inhibit the Syrian government’s ability to use attack helicopters on rebel-held towns and villages. Indeed, already in the days following the incident, some activists reported a drop in government air attacks in Idlib.

Syrian regime bombards Idlib Show all 23 1 /23 Syrian regime bombards Idlib Syrian regime bombards Idlib Members of the Syrian Civil Defence, also known as the White Helmets, recover a wounded boy from the rubble of a building following a regime air strike on a vegetable market in Syria's last major opposition bastion of Idlib AFP via Getty Syrian regime bombards Idlib The regime air strikes killed at least nine civilians, striking bustling areas of Idlib city AFP via Getty Syrian regime bombards Idlib An injured woman waits to receive treatment at a makeshift hospital AFP via Getty Syrian regime bombards Idlib Syrian Civil Defence, also known as the White Helmets, searching through the rubble of a building AFP via Getty Syrian regime bombards Idlib A Syrian boy is evacuated AFP via Getty Syrian regime bombards Idlib A drone picture taken on January 15, 2020, shows members of the Syrian Civil Defence, also known as the White Helmets, searching through the rubble of a building at the site of a regime airstrike on Syria's last major opposition bastion of Idlib - Regime air strikes on Syria's last major opposition bastion killed at least nine civilians, striking bustling areas of Idlib city despite a fresh Russian-sponsored truce, a war monitor said. At least 20 other civilians were wounded in the raids that hit a vegetable market and repair shops in Idlib, capital of the jihadist-held province of the same name, said the Syrian Observatory for Human Rights. (Photo by Omar HAJ KADOUR / AFP) (Photo by OMAR HAJ KADOUR/AFP via Getty Images) OMAR HAJ KADOUR AFP via Getty Images Syrian regime bombards Idlib The wreckage of a car AFP via Getty Images Syrian regime bombards Idlib A Syrian boy cries as he is evacuated AFP via Getty Images Syrian regime bombards Idlib Rescuers search for survivors EPA Syrian regime bombards Idlib A drone picture taken on January 15, 2020, shows members of the Syrian Civil Defence, also known as the White Helmets, searching through the rubble of a building at the site of a regime airstrike on Syria's last major opposition bastion of Idlib - Regime air strikes on Syria's last major opposition bastion killed at least nine civilians, striking bustling areas of Idlib city despite a fresh Russian-sponsored truce, a war monitor said. At least 20 other civilians were wounded in the raids that hit a vegetable market and repair shops in Idlib, capital of the jihadist-held province of the same name, said the Syrian Observatory for Human Rights. (Photo by Omar HAJ KADOUR / AFP) (Photo by OMAR HAJ KADOUR/AFP via Getty Images) OMAR HAJ KADOUR AFP via Getty Images Syrian regime bombards Idlib A Syrian boy grimaces in pain after he was wounded in the airstrikes AP Syrian regime bombards Idlib A Syrian youth stands at the site of a regime air strike in Ariha town AFP via Getty Syrian regime bombards Idlib Rescuers search for survivors under the rubble of a collapsed building EPA Syrian regime bombards Idlib A Syrian walks on the rubble of a building following a regime air strike on Ariha town in Syria's last major opposition bastion of Idlib on January 15, 2020. - Regime air strikes on Syria's last major opposition bastion killed at least nine civilians Wednesday, striking bustling areas of Idlib city despite a fresh Russian-sponsored truce, a war monitor said. (Photo by Omar HAJ KADOUR / AFP) (Photo by OMAR HAJ KADOUR/AFP via Getty Images) OMAR HAJ KADOUR AFP via Getty Syrian regime bombards Idlib Firefighters try to extinguish flames EPA Syrian regime bombards Idlib Emergency services look for survivors AP Syrian regime bombards Idlib Emergency services look for survivors after airstrikes in the city of Idlib, Syria, Wednesday, Jan. 15, 2020. Syrian government warplanes struck a market and an industrial area Wednesday in the last territory in the hands of rebel groups in the country's northwest, killing at least 15 people, opposition activists said. (AP Photo/Ghaith Alsayed) Ghaith Alsayed AP Syrian regime bombards Idlib A boy wounded in airstrikes is treated in a hospital AP Syrian regime bombards Idlib Syrian White Helmet civil defense workers extinguish a burning car Syrian Civil Defense White Helmets via AP Syrian regime bombards Idlib A Syrian walks on the rubble of a building AFP via Getty Syrian regime bombards Idlib People walk past destruction by the government airstrikes in the town of Ariha, in Idlib province, Syria, Wednesday, Jan. 15, 2020. Syrian government warplanes struck a market and an industrial area Wednesday in the last territory in the hands of rebel groups in the country's northwest, killing at least 15 people, opposition activists said. (AP Photo/Ghaith Alsayed) Ghaith Alsayed AP Syrian regime bombards Idlib People walk past destruction by the government airstrikes in the town of Ariha, in Idlib province, Syria, Wednesday, Jan. 15, 2020. Syrian government warplanes struck a market and an industrial area Wednesday in the last territory in the hands of rebel groups in the country's northwest, killing at least 15 people, opposition activists said. (AP Photo/Ghaith Alsayed) Ghaith Alsayed AP Syrian regime bombards Idlib People look at destruction by the government airstrikes in the town of Ariha, in Idlib province, Syria, Wednesday, Jan. 15, 2020. Syrian government warplanes struck a market and an industrial area Wednesday in the last territory in the hands of rebel groups in the country's northwest, killing at least 15 people, opposition activists said. (AP Photo/Ghaith Alsayed) Ghaith Alsayed AP

Throughout the course of the nearly nine-year conflict, foreign backers of Syrian rebel groups have tried to restrict the delivery of the missiles – also known as man-portable air defence systems (Manpads) – over concerns that they may fall into the hands of terror groups, who could use them to bring down civilian airliners.

Turkey backs a number of rebel groups inside Syria who are currently fighting alongside the jihadist Hayyat Tahrir al-Sham, a former affiliate of al-Qaeda, which has been the target of US airstrikes.

In the past, the US has urged its allies to restrict the delivery of Manpds to Syrian rebels. They have been used by rebel fighters a number of times, however. In 2018, a Russian Sukhoi Su-25 was shot down using the missile system over Idlib.

The downing of the helicopter comes amid the most serious clashes between Turkish forces and Syrian government troops in the course of the entire conflict.

Syrian troops launched a new push in December to recapture the last rebel-held bastion of Idlib, forcing hundreds of thousands of civilians to flee.

In recent days, the renewed push has brought Syrian troops into direct confrontation with Turkey. Thirteen Turkish military personnel have been killed by Syrian government shelling in the past 10 days. Turkey claimed to have killed 52 Syrian soldiers in response, and the country’s president vowed more reprisals if any more Turkish troops were harmed.

“If there is the smallest injury to our soldiers on the observation posts or other places, I am declaring from here that we will hit the regime forces everywhere from today, regardless of Idlib’s borders,” Recep Tayyip Erdogan said.

“We will do this by any means necessary, by air or ground, without hesitating, without allowing for any stalling,” he added.

Charles Lister, director of the Countering Terrorism & Extremism programme at the Middle East Institute, said the use of Manpads may signal a more muscular approach from Turkey towards the current crisis in Idlib.

“It’s possible, or even most likely, that the Manpad used was already in theatre and wasn’t a recent gift from the Turks, but that’s frankly academic. Amid rumours and threats, a Syrian aircraft was shot down,” he told The Independent.

“That by itself contributes towards Turkish efforts to insert some more meaningful deterrence amid an environment in which it, and the opposition, have struggled to maintain much control or influence.”

In recent days, Turkey has appealed to Russia to halt the Syrian government offensive. On Thursday, the Turkish defence minister said his country’s military would target rebel groups that violated a ceasefire in Idlib.

“Force will be used against those violating the ceasefire, including radicals, and every measure will be taken,” Hulusi Akar said, referring to a 12 January ceasefire Ankara says has been violated by Assad’s forces.

Ankara has deployed more than 1,000 troops to its military posts in Idlib since last week.

On Wednesday, Mr Erdogan said Ankara had given a message to the rebels it supports in the conflict to refrain from acting in an “undisciplined” way and giving Syrian forces an excuse to strike.

The rebels are a mix of nationalist factions and Islamist militants who have had deadly rivalries but are now closing ranks.

Ankara and Moscow back opposing sides, but have collaborated on a political solution to the war.