Story highlights

NEW: "A political solution to the crisis in Syria is more needed than ever," and commitment to Turkey is "rock solid," NATO chief says

Syrian official: Russian strikes have "diminished the fighting capacity of ISIS and other terrorist groups"

Russia says it fired 26 missiles from the Caspian Sea into Syria

CNN  — 

The Syrian regime, which had appeared earlier this year to be on the ropes, has “launched a wide-scale offensive,” a senior military official said Thursday.

The aim is “eliminating the terrorist groups and liberating the areas and towns that have suffered from terrorism and its crime,” Gen. Ali Abdullah Ayyoub, the Syrian army chief of staff, said on state media,

Ayyoub provided no details of the area in which the offensive is being launched or its size and scope.

But he acknowledged the key role being played by Russia, which appears bent on supporting a Syrian regime that had been badly in need of help.

“Following the Russian military airstrikes that diminished the fighting capacity of ISIS and other terrorist groups, the Syrian armed forces maintained their military initiative,” Ayyoub said.

Russia launches 26 missiles from Caspian Sea

Russia has dramatically altered the balance of power in the Middle East with its robust intervention in the Syrian civil war. On Wednesday, it launched a naval bombardment of ISIS targets in Syria, a senior Russian official said, ramping up its newly muscular presence in the Middle East.

Russia says it launched missiles at Syrian targets from the Caspian Sea.

Four Russian ships fired 26 missiles into Syria, hitting 11 targets, Russian Defense Minister Sergei Shoigu told President Vladimir Putin during a televised meeting.

Shoigu said the strikes were launched from the Caspian Sea using precise long-range missiles that flew 1,500 kilometers (930 miles) to their targets.

Wednesday also appeared to mark new and closer military cooperation between Russia and the embattled Syrian regime of President Bashar al-Assad.

Russia and Syria launched coordinated attacks Wednesday on Islamist factions in towns in Hama and Idlib provinces in western Syria, with the Syrian shelling apparently conducted in concert with Russian airstrikes, according to an opposition group.

Why are Russian airstrikes in Syria a big deal?

If the report is correct, it could offer fresh evidence that Russia’s primary goal is propping up al-Assad rather than fighting terrorism.

Russian airstrikes in Syria from September 30 to October 5

Even as its ships and warplanes conducted fresh strikes, Russia said it was willing to cooperate with the United States in carrying out attacks in Syria.

However, speaking to reporters in Rome, U.S. Defense Secretary Ashton Carter called the Russian campaign of airstrikes in Syria a “fundamental mistake.” He said the United States was not ready to cooperate with Russia on operations in Syria.

The U.S. military recently had to divert one aircraft over Syria to ensure it could maintain a safe flying distance from a Russian fighter, a Pentagon representative said. Until the two countries agree on mutual flight safety rules in Syrian airspace, U.S. pilots are under orders to change their flight path if a Russian plane is within 20 nautical miles, a senior defense official told CNN.

Opposition group reports fierce clashes

Russian warplanes conducted heavy airstrikes Wednesday on Islamist factions, accompanied by shelling from government forces, according to the UK-based, anti-Assad Syrian Observatory for Human Rights.

The head of the observatory said there were no ISIS positions in the areas targeted and that fierce clashes were taking place on the ground between regime forces and their allies and armed Islamist rebel factions, including the Ahrar al-Sham and al Qaeda-affiliated al-Nusra Front.

Wednesday’s clashes are the fiercest in the last month, the observatory said.

Russia has said it is targeting ISIS, al-Nusra Front and “other terrorist groups” as recognized by the U.N. Security Council or Russian law.

Syria’s ambassador to Russia, Riad Haddad, said Wednesday that around 40% of ISIS infrastructure had been destroyed since Moscow’s military operation began, Russia’s state-run Sputnik International reported.

‘Substantial military buildup’

But Turkey, Syria’s neighbor to the north, cast fresh doubt Wednesday on whether Russia’s goal was to go after SIS.

A fraction – 3.5% – of Russia’s airstrikes in Syria so far have targeted the terror group, Turkish Prime Minister Ahmet Davutoglu said.

NATO chief Jens Stoltenberg condemns Russia's incursion into Turkish airspace.

On Thursday, NATO Secretary-General Jens Stoltenberg called recent violations of Turkish airspace unacceptable and said the alliance stood ready to help Turkey protect itself.

Speaking after a meeting of NATO defense ministers in Brussels, Belgium, Stoltenberg said the alliance was in constant dialogue with Turkey, and its determination to help Turkey defend itself was “rock solid.”

“A political solution to the crisis in Syria is more needed than ever,” he said.

“These air raids are not against ISIS. There were 57 air raids by Russian air forces. Fifty-five of them were against moderate opposition and only two were against Daesh, according to military information we received,” Turkey’s Anadolu news agency quoted Davutoglu as saying, reflecting government thinking. Daesh is another name for ISIS.

“So what we’ve seen in initial airstrikes that Russia carried out beginning last week were primarily targeting places where ISIL wasn’t ensconced, didn’t exist, didn’t have a presence and frankly it was where moderate Syrian opposition forces are generally located,” deputy spokesman Mark Toner told reporters Wednesday, referring to ISIS with another acronym.

6 graphics that explain the latest on the war in Syria

The developments came a day after NATO’s secretary general expressed alarm over how the Russian military had grown on several fronts in Syria, including boots on the ground.

“It’s unacceptable, it’s dangerous, and it’s reckless behavior and it adds to the tensions,” Secretary General Jens Stoltenberg told CNN about the incursions into Turkish airspace.

Stoltenberg said he doubted that Russia was interested primarily in fighting ISIS.

“I’m also concerned that Russia is not targeting ISIL but instead attacking the Syrian opposition and civilians,” he said.

In addition to the incursion reports, the Turkish air force said a MiG-29 fighter jet of an unidentified nationality had interfered Monday with eight Turkish F-16s on the Turkey-Syria border. The Turkish air force reported the jet put its planes under a radar lock for four minutes and 30 seconds.

The latest U.S. assessment indicates that Russia has moved ground combat weapons and troops to operate them into areas of western Syria where anti-regime forces are, according to two American defense officials. The United States sees the move as Russia “stepping up its ground activity” in Syria to attack those forces, rather than ISIS elements, according to one of the officials.

But Russian officials deny ramping up military activity. Officials quoted by state media said there would be no ground operation in Syria and – in contrast to what officials had said earlier – Russia would try to prevent any “volunteers” from going to Syria.

Opinion: Putin’s Syria moves leave U.S. looking weak

CNN’s Hala Gorani, Hamdi Alkhshali and Michael Martinez contributed to this report.