Two Russian warships crossed Turkey's Bosphorus Strait early Tuesday headed towards the Black Sea, Turkish media reported.
The reported ship movements came with Russia and the West locked in a standoff over Ukraine's Crimean peninsula on the Black Sea.
Turkey's state run Anatolia news agency, carrying a picture of one of the warships, said Russia had "summoned" the vessels back to its Black Sea fleet to strengthen its military presence in Crimea.
A Ukranian vessel was also seen crossing the Dardanelles Strait off Turkey's west coast and was expected to cross into the Black Sea, the agency said.
The Turkish military also said that it scrambled eight F-16 jets on Monday after a Russian spy plane was detected flying parallel to its Black Sea coast.
Turkey, a NATO ally, has repeatedly voiced fears about the fate of the Turkish-speaking Tatar minority in Crimea, which was part of the Ottoman Empire until it was conquered by Russia in the late 18th century.
Also on Tuesday, Russia carried out a successful test launch of an "advanced" intercontinental ballistic missile, state news agencies reported amid a fierce standoff between Moscow and the West over Ukraine.
"The purpose of the launch is to test the advanced payload of the intercontinental ballistic missile," Russia's three main news agencies quoted a top defense official as saying.
But the official said Russia informed the United States earlier this week that it would carry out the test launch.
"We have been notified of this test earlier this week. It's not unexpected," the defense official, who spoke on condition of anonymity, told Agence France Presse.
He said the launch involved the RS-12M Topol -- a road-mobile missile last reportedly tested by Russia on December 28.
The missile was first put into service in the 1980s and then repeatedly modified. It is referred to as the SS-25 Sickle by NATO and has a reported maximum range of 10,000 kilometers (6,200 miles).
The defense official provided no details of the missile's advanced features, saying only that it was launched from Russia's Kapustin Yar rocket launch site near the southern city of Volgograd.
The missile successfully hit its target in the Sary Shagan ballistic missile test range that Russia leases in Kazakhstan.
Russia has been testing warheads that could evade a missile defense shield the United States is deploying together with NATO in Europe over Russia's strong objections.
The Russian defense official said the test was designed to check the warhead's ability to "penetrate missile defense systems".
Meanwhile, Russian forces fired warning shots on Ukrainian soldiers at a base near Sevastopol as tensions flared in the standoff over Crimea.
Pro-Russian troops guarding an airfield in Belbek, near Sevastopol, fired the shots in the air as a column of about 300 Ukrainian troops approached around 9:00 am local time (0700 GMT), Oleksey Khramov, an officer at the base, told AFP.
"They fired several shots into the air and said they would open fire if they continued to approach," he said.
The Ukrainian soldiers, who were unarmed, then stopped to avoid a confrontation, he said.
In footage of the incident shown on Britain's Sky Television, a pro-Russian soldier told the approaching Ukrainians: "Hold back. I want your officer here! We'll be shooting your legs."
A Ukrainian soldier replied: "You will pay for this, you'll be held responsible."
The Russian soldier told the Ukrainian soldiers to "calm down" and accused them of "deliberately provoking us".
An AFP reporter at the base said the column of troops had since returned inside the administrative base of the Sevastopol tactical aviation brigade in Belbek, where dozens of Ukrainian soldiers are holed up refusing to abandon their posts.
Russian forces have surrounded Ukrainian military bases across Crimea as the Russian-speaking autonomous region has been thrown into turmoil following the ouster last month of Moscow-backed president Viktor Yanukovych.
Tensions are high, but fears of an imminent assault by Russian forces did not materialize overnight.
"The night was quiet," Vladyslav Seleznyov, the defense ministry spokesman for Crimea, told AFP in the regional capital Simferopol.
Ukrainian officials said Monday that Russia had given Ukrainian soldiers in Crimea an ultimatum to surrender or face an all-out assault, although Russia denounced the claim as "complete nonsense".
"No more declarations have been made by the Russian side," Seleznyov said.
In Sevastopol, a bastion of pro-Kremlin sentiment, pro-Russian activists had surrounded the headquarters of the Ukrainian navy in Crimea.
An AFP reporter said about 100 pro-Russia activists were gathered outside the offices and formed a human chain, as Russian forces with automatic rifles stood nearby.
Seleznyov said Russian vessels were also blocking Ukrainian warships from trying to leave the port, which has been the home of the Russian navy's Black Sea fleet for some 250 years.
The Ukrainian defense ministry says several thousand Russian troops have been sent by the Kremlin to Crimea.
Russian President Vladimir Putin on Tuesday denied that Russian forces were operating in Crimea, saying that only "local forces of self-defense" were surrounding Ukrainian military bases.
Armed men believed to be under Moscow's orders last week seized key government buildings in Crimea and airports on the peninsula.
Regional lawmakers deposed the Kiev-supporting prime minister and have called for a referendum on March 30 on proclaiming greater autonomy for Crimea.
