* Most of Crimea under control of Russia's military
* Ukrainian ship fails to break Russian naval blockade
* Defence Ministry says bases formally under Ukrainian control (Adds details, quotes)
By Aleksandar Vasovic and Gabriela Baczynska
SEVASTOPOL/PEREVALNOYE, Crimea, March 21 (Reuters) - Unlike the unmarked masked soldiers who first seized Crimea three weeks ago, Russian paratroopers strolling across a field near the peninsula's Perevalnoye military base, which they took over on Friday, wore their trademark blue berets and red star cockades.
In other parts of Crimea, Russian troops continued the takeover of Ukrainian positions.
The taking of the Perevalnoye base, 25 kilometres (15 miles) southeast of the capital Simferopol, coincided with the expiry of a truce between Ukrainian and Russian defence ministries made last week after the annexation of predominantly ethnic-Russian Crimea.
"Yes, we are Russians. We are brotherly troops here," said an officer before entering a field camp metres away from Ukrainian positions.
The Russian takeover of the Black Sea peninsula has been largely bloodless, though one Ukrainian serviceman was killed and two others wounded in a shooting in Simferopol earlier this week.
A Defence Ministry spokesman in Kiev said Crimea's bases were still under Ukrainian control. "Formally, all military facilities on Crimea are under the control of Ukrainian armed forces. Everything else is speculation," he said.
At Donuzlav Bay, a Black Sea inlet northwest of Sevastopol, Ukraine's minesweeper Cherkasy attempted without success to break to the open sea through a blockade at the entrance to the bay made of three hulks, scuttled by the Russian navy earlier this month.
A Reuters cameraman saw two Russian helicopters flying over the Ukrainian ship and an infantry unit was deployed along the shoreline. The Cherkasy and another five ships were blocked by the sunken Russian vessels.
In Perevalnoye, several dozen soldiers and their families were seen packing and leaving.
Russian troops have also moved to the isolated compound of a previously defiant Ukrainian air-mobile unit in Perevalnoye. Smiling Russian soldiers were seen at the compound's gate, above which the Russian tricolour and yellow-green standard of the paratroopers fluttered in the wind.
Ukrainian troops could not be seen through the open gate, and it was not immediately clear whether they had left through another exit. Previously, a serviceman said talks negotiating their departure were ongoing.
Defence analysts in Kiev say there are between 8,000 and 10,000 Ukrainian troops deployed at about three dozen bases across Crimea, but the Ukrainian military estimates there are up to 20,000 of their troops on the peninsula.
In the Belbek air base, which has so far refused to surrender, some Ukrainian soldiers were seen leaving in pairs or threes, or packing bags and home appliances into cars. Others said they would remain inside until the end.
"We have said goodbyes to our families. There were tears, but now we are ready," Sergei, a soldier, said through the fence, pointing a finger to his forehead, imitating a shot to the head.
Many troops in the Belbek airbase carried weapons, but no magazines were loaded. Some hoped they would be able to give up the base honourably and without bloodshed.
Nikolai, a middle-aged serviceman in camouflage fatigues, complained about a lack of orders from the higher command in Kiev and said he was willing to continue to serve in the Ukrainian forces.
"We repeatedly asked Kiev for orders, and it was radio silence, as if they were afraid to take responsibility for us," he said. "The Russians will come, there will be some noise, and that's it, hopefully. We don't plan to die here," he said.
On Thursday, Russian troops in the Crimean naval base of Sevastopol seized three Ukrainian corvettes, Lutsk, Khmelnitsky, and Ternopol, following the takeover of the naval headquarters there a day earlier.
Slavutych, the command ship of the Ukrainian fleet remained anchored in the main port of Sevastopol on Friday, blocked by three Russian auxiliary vessels and the missile cruiser Moskva. (Writing by Aleksandar Vasovic; Additional reporting by Dimitry Madorsky, Olga Petrova in Donuzlav and Pavel Polityuk in Kiev; Editing by Alessandra Prentice and Will Waterman)