Russian warships opened fire on targets in Syria launching cruise missiles from the Caspian Sea. This video was released by Russia's defense ministry. (Russian Defense Ministry/YouTube)

Russia’s Caspian Sea fleet on Wednesday launched a complex cruise missile strike against Syrian rebels from nearly 1,000 miles away, a potent exhibition of Moscow’s firepower as it backs a government offensive in Syria’s multi-faction civil war.

The bombardment was the first naval salvo of Russia’s week-old military intervention in Syria, where it has already launched more than 100 airstrikes against the Islamic State and factions of Islamist and U.S.-backed rebel forces opposed to President Bashar al-Assad.

The attack showcased Russia’s advanced military capabilities and closer coordination with the governments of Iran and Iraq, whose airspace the missiles traversed before striking targets in Syria held by the Islamic State and Jabhat al-Nusra, an affiliate of al-Qaeda.

Like Russia, Iran is a key backer of Assad. Iraq’s leadership has close ties with Iran but also depends on support from the United States and Western allies.

Russian Defense Minister Sergei Shoigu said in a nationally televised briefing that the ships launched 26 cruise missiles, destroying 11 targets and killing no civilians. He also said that Russian planes continued to carry out airstrikes Wednesday.

The naval strikes on Wednesday were the first known operational use of state-of-the-art SSN-30A Kalibr cruise missiles, which were still being tested by the Russian navy in August.

Russian President Vladimir Putin said the strikes spoke to the professionalism of Russia’s revamped army.

“We know how difficult it is to carry out this kind of anti-terrorist operation,” Putin told Shoigu. “Of course, it is early to draw conclusions. But what has been done so far deserves a highly positive assessment.”

The strikes came as Syrian troops backed by Russian air power launched their first major ground offensive since Moscow began its intervention in the conflict Sept. 30.

News reports and video of fighting uploaded to the Internet on Wednesday showed that the Syrian army was moving from the city of Hama toward Idlib, a stronghold held by a coalition of mostly Islamist rebels.

While the Kremlin’s stated aim in the conflict is to fight the Islamic State in Syria, the United States and its allies say Russia is concentrating its firepower against other rebel groups to prevent Assad from being overrun. One video on Wednesday appeared to show the Free Syrian Army, a moderate force backed by the West, firing anti­tank missiles at government troops advancing with Russian air support.

“Russia is targeting civilians and the Free Syrian Army brigades that are supported by America. They are not targeting the Islamic State as they claimed,” said Raed Fares, a Syrian activist in Idlib. “Russia is here to keep Assad in power, so they will strike what Assad strikes.”

In televised remarks on Wednesday, Putin encouraged the Free Syrian Army to join an alliance with Assad’s troops against the Islamic State. At the same time, he belittled the influence of moderate rebels on the conflict.

“True, we don’t currently know where it is and who is leading it,” Putin said of the Free Syrian Army.

Russian news reports Wednesday said Syrian forces launched a heavy artillery bombardment and were moving toward Idlib, but they added that it was not yet clear how far the Syrian troops had advanced.

The news reports also said Syrian troops used advanced rocket-launch systems similar to the ones that Western officials say Moscow shipped to Syria last week.

In a video posted to YouTube from the town of Kafranboudah, in the western part of the Hama countryside, a Syrian rebel commander said government forces­ began shelling his unit’s position on the front line early Wednesday. Kafranboudah is about 16 miles east of Latakia province, a Syrian regime stronghold. More than a dozen rebel groups formed a coalition to oust government forces­ from Hama in August.

Regime soldiers on Wednesday stormed the town from three sides with Russian air support, the rebel commander said, and the fighting has extended nearly 20 miles southeast to the town of Maan. He did not say whether his fighters suffered any losses­ but said Syrian rebels destroyed at least four regime tanks with anti­tank missiles.

The West, which has launched more than 7,000 airstrikes against the Islamic State in the past year, has bristled at Moscow’s military build­up in Syria. Russia has deployed surface-to-air missiles, fighter jets and radar-jamming equipment that officials say is meant to interfere with Western forces.

On Tuesday, U.S. and Russian officials tentatively agreed to resume talks on how to coordinate in the skies over Syria. Turkey, a NATO member that shares a border with Syria, has already accused Russia of violating its airspace.

In Rome, Defense Secretary Ashton B. Carter did not respond directly when asked by reporters about the Russian military’s apparent support for the Syrian government’s ground offensive.

But the Pentagon chief for the first time ruled out any cooperation with Moscow in the fight against the Islamic State, saying that Russia’s strategy was clearly just to support Assad and his government.

“We believe Russia has the wrong strategy. They continue to hit targets that are not ISIL. This is a fundamental mistake,” Carter said, using one of the acronyms for the Islamic State.

In the past, the Obama administration has publicly held out hope — however faint — that Moscow might cooperate in the military campaign against the Islamic State.

In his most hard-line comments to date about Russia, Carter rejected the possibility of teaming up with the Russians in that regard. He said the Pentagon still wanted to talk with Moscow about finding ways to manage the crowded airspace above Syria and avoid any hostile or inadvertent encounters. “That’s it,” he said flatly.

There have been no reported close encounters or unsafe incidents involving U.S. and Russian warplanes so far in Syria, according to a senior U.S. defense official who spoke on the condition of anonymity to discuss military operations.

Russian aircraft have “come closer” to U.S. drones on at least one occasion, the official said, but it was not a dangerous incident.

“Certainly they are in similar battle space, so they see each other and they are aware of each other,” the official said of Russian and U.S. warplanes.

Pentagon officials have said the Russian intervention in Syria has not forced the U.S. military or its coalition partners to alter the rate or location of their surveillance missions and airstrikes against the Islamic State.

The two sides have jousted in recent days over the conditions for holding another round of talks. Washington wants to limit the discussion to technical factors about aviation safety, while Moscow has said it wants a broader conversation about possibly coordinating military operations — something the Pentagon steadfastly opposes.

The senior U.S. defense official said the Pentagon drafted a document last week for the Russians that lays out “basic rules of flight conduct,” such as what language and radio frequencies pilots would use in a hostile or inadvertent encounter.

The Russians have not responded to any of the particulars, the official said.

Cunningham reported from Beirut. Craig Whitlock in Rome, Hussam Alrefaie in Beirut, Heba Habib in Cairo, and Thomas Gibbons-Neff and Brian Murphy in Washington contributed to this report.

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