A Top Iranian General Has Been Killed by the Islamic State in Syria

An Iranian Revolutionary Guards general has been killed near Aleppo, where he was advising the Syrian army on their battle against Islamic State (IS) fighters, the guards said in a statement on Friday.

The Guards said General Hossein Hamedani was killed on Thursday night and that he had "played an important role … reinforcing the front of Islamic resistance against the terrorists."

Meanwhile, IS has seized villages close to Aleppo from rival insurgents, a monitoring group said on Friday, despite a Russian air-and-sea campaign that Moscow says has targeted the militant group.

The Russian defense ministry said air strikes on rebel positions in northern Syria had killed 300 anti-Assad insurgents in nearly 70 sorties over the last day. There was no independent confirmation of the death toll.

The RIA news agency said 200 insurgents were killed in an attack on the Liwa al-Haqq rebel group while 100 were killed in Aleppo. Two IS field commanders were among the dead, the defense ministry was quoted as saying.

The UK-based Syrian Observatory for Human Rights (SOHR), which monitors the fighting on the ground, said there had been no significant advances by government forces backed by allied militia in areas where ground offensives were launched this week. "It's back and forth," said Rami Abdulrahman, SOHR director.

IS is now within one mile of government-held territory on the northern edge of Aleppo which has suffered widespread damage and disease during the four-year civil war that erupted in the wake of protests against Assad.

Syria's military, backed by Russia, Iran and allied militias, has launched a major attack in Syria's west to recapture land lost to non-IS rebels near the heartland of Assad's minority Alawite sect, an area vital to his survival.

As the operation in the west pushed ahead, IS said its fighters had captured five villages in its northern offensive and killed more than 10 soldiers or militiamen.

SOHR said it was the biggest IS advance since it launched an offensive against rival rebels in the Aleppo countryside near the Turkish border in late August.

Iran is the main regional ally of Syrian President Bashar al-Assad, and has provided military and economic support during Syria's four-year-old civil war. Tehran denies having any military forces in Syria, but says it has offered "military advice" to Assad's forces in their fight against "terrorist groups."

Hamedani was a veteran of the 1980-88 Iran-Iraq war and was made deputy chief commander of the elite forces in 2005.

In the biggest deployment of Iranian forces yet, sources told Reuters last week that hundreds of troops had arrived since late September to take part in a major ground offensive planned in west and northwest Syria.

Iranian lawmaker Esmail Kosari said Hamedani helped coordination between Syrian armed forces and the voluntary forces in their fight against IS.

"For years, Hamedani played a very important role in Syria as an adviser… he played an important role in preventing the fall of Damascus. Then he returned home at the end of his assignment," Kosari told the semi-official Tasnim news agency.

"He returned to Syria for a few days because of his deep knowledge about the area … and he was martyred in Syria."

Related: Iran's Supreme Leader Bans Further Negotiations with United States

Assad's longtime ally, Russia launched its air campaign in September, saying it would also target IS. But its planes have also hit other rebel groups opposed to Assad, including groups backed by Washington.

The United States and its allies have been waging a year-long air campaign against IS in Syria, while pushing to diplomatically edge Assad from power.

Washington has ruled out military cooperation with Russia in Syria, accusing Moscow of pursuing a "tragically flawed" strategy that would force it to limit military talks to basic pilot safety.

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