BEIRUT/DAMASCUS: Syrian insurgents are deploying extensive supplies of anti-tank missiles provided by their foreign backers to counter ground attacks by the Syrian army and its allies, backed by heavy Russian airstrikes, rebel commanders said Tuesday.

Two rebel commanders contacted by Reuters declined to confirm whether they had received additional missiles since the Russian airstrikes began, but said they had “excellent” supplies and were stationing them along a 30-km front to halt the ground offensive.

Activists, however, said supplies had been stepped up since the Russian airstrikes began on Sept. 30.

With Russian air support and help from Lebanon’s Hezbollah and Iranian soldiers, with Quds Force commander Maj. Gen. Qasem Soleimani also believed to be in the country, the Syrian army is trying to drive rebels from western areas that are crucial to President Bashar Assad’s survival, and has recaptured several towns in the provinces of Hama and Latakia.

Russia’s 2-week-old air campaign has bolstered Assad and left the United States struggling to adjust its troubled military support program for Assad’s opponents. On the ground, however, the Syrian army is not making rapid gains.

The Syrian Observatory for Human Rights, a Britain-based group tracking the war, said a battle was in progress for control of the town of Kafr Nabouda in Hama province, which the army said it captured Monday. At least 25 fighters on the government’s side were killed, it said. The town marks the western edge of the defensive line along which the rebels have stationed a dozen anti-tank missile launch platforms, said Ahmed al-Seoud, head of the 13th Division, a foreign-backed faction fighting under the umbrella of the Free Syrian Army. “They are highly effective. They are breaking the Russian-Iranian and Syrian army.” Foreign states opposed to Assad have supplied the TOW guided missiles to a number of rebel groups via an operations room in Turkey, one of the states in the region that wants Assad gone.

The missiles have been widely seen as important to rebel advances earlier this year that had put Assad under pressure.

The Observatory’s director, Rami Abdel-Rahman, said the rebels were using significant numbers of TOWs. “It increased in the last days, and it has proved its effectiveness.”

Ibrahim al-Idlibi, an activist who acts as media adviser to several FSA groups in northern Syria, said several dozen army vehicles had been destroyed by TOW missiles in recent days.

Fares al-Bayoush, a former Syrian army colonel who heads the Fursan al-Haq group, also spoke of a battery of TOW missile platforms stretching east along the front line from Kafr Nabouda to the village of Maan.

The aim is to stop government forces advancing north from Morek to rebel-held Khan Sheikhoun, both towns on a north-south highway linking the city of Hama to Aleppo and Idlib, and also to attack.

Echoing the objective to go back on the offensive, an alliance of insurgents that has been targeted by Russian airstrikes said Tuesday it was starting an operation to recapture Hama. The Army of Conquest, which captured most of the neighboring Idlib province in May, includes Al-Qaeda’s Syria wing Nusra Front, the Islamist Ahrar al-Sham faction and groups including Chechen and central Asian fighters. But it will struggle to advance in the face of the Russian airstrikes and Syrian army assault, Abdel-Rahman said.

Both sides have sent reinforcements to the area. Hezbollah has redeployed all its fighters in Syria to take part in the battle in the northwest, according to sources familiar with political and military developments in Syria.

Abdel-Rahman said insurgents sent to Kafr Nabouda – many of them from extremist groups – had helped prevent the army from recapturing the town.

Rebel fighters and weapons also arrived in the strategically important Sahl al-Ghab plain Monday, a rebel fighter in the area said. He said one of the groups there was also using TOW missiles.

Two shells landed near the Russian Embassy in Damascus Tuesday, while a small pro-Moscow demonstration was taking place, but there were no reports of casualties or damage to the embassy building.

Israeli artillery also targeted Syrian army posts after two rockets fired from Syria hit the Israeli-occupied sector of the Golan Heights, Israel said.

Russia’s Defense Ministry said its warplanes carried out 88 sorties in the last 24 hours, one of the biggest totals of its campaign, targeting 86 sites in Raqqa, Hama, Idlib, Latakia and Aleppo provinces.

It said ISIS units lost most of their ammunition and heavy weapons as a result of the airstrikes – a claim that was not independently confirmed.

A spokesman for ISIS, Abu Mohammad al-Adnani, vowed in an audio message that Russia, like the U.S., will be defeated.

The Russian intervention in the 4-year-old Syrian war has caught U.S. President Barack Obama’s administration off-guard. U.S. Defense Secretary Ash Carter said Tuesday that the United States expects an agreement with Russia’s military soon on air safety protocols in the skies above Syria.

Carter said the next round of talks between the U.S. and Russian militaries would take place Wednesday.