The targeted groups include various Western-backed fighters.
Other activists wondered where the Americans were.
The Observatory’s chief Rami Abdurrahman and Raqqa is Being Silently Slaughtered say a training facility, known as Vanguards Camp, was hit on the southern edge of the city. It said the attack is believed to have been carried out by Islamic State militants.
“Militants are sustaining substantial losses under the Russian airstrikes and are having to change their tactics, to scatter their forces, to carefully disguise themselves and hide in settlement,” he said.
The Russian bombing campaign appears to have weakened these groups, and given IS the opportunity to push forward, he adds.
Islamic State are presently in just one kilometer (a singular mile) of government-held place on Aleppo’s urgent creep, the closest as compared to to the metropolitan area.
Senior Iranian officials have been in Syria for several years as military advisers.
“IS has never been so close to the city of Aleppo, and this is its biggest advance towards” the country’s pre-war commercial capital, said Abdel Rahman, whose Britain-based group relies on a network of sources on the ground across Syria.
He said Russian Federation had bombed a command post in IS stronghold Raqa, killing two senior commanders and around 200 fighters, according to intercepted radio communications.
One of those groups, Liwa Suqour al-Jabal, said Russian strikes destroyed their main weapons depot this week.
“Daesh has exploited the Russian air strikes and the preoccupation of the (rebel) Free Syrian Army in its battles in Hama, and advanced in Aleppo”, said one rebel commander with fighters in the region, using an Arabic name for IS.
Iranian military commander Brigadier General Hossein Hamedani has been killed by the Islamic State of Iraq and the Levant (ISIL) on the outskirts of the Syrian city of Aleppo, Iran’s army has said.
“General Hamedani, who advised the Syrian army, was killed in Aleppo yesterday evening”, the statement said.
Iran declined to confirm the claim by the USA official, who did not provide details about where the missiles might have come down or if they caused any damage.
Abdurrahman said he was killed on the edge of the Kweiras military airbase, which the Daesh group has besieged for months. Syrian troops launched an offensive last week in an attempt to break the siege.
Kweiras base is about 50km away from the area of the Daesh offensive Thursday night.
The president also extended condolences to Supreme Leader of the Islamic Revolution Ayatollah Seyed Ali Khamenei, the Armed Forces, particularly the IRGC forces, and to all Iranians. “I think the primary Iranian objective is to ensure that Assad does not fall”.
The Obama administration is grappling with a dramatic change in the four-year-old Syrian civil war brought about by Moscow’s intervention in support of President Bashar al-Assad.
Assad hails from Syria’s Alawite religious minority, an offshoot of Shiite Islam. Two Islamic State commanders were among the dead in Russia’s most intense raids since it launched strikes in Syria 10 days ago.