SIMFEROPOL, Ukraine (CNN) -- Russia accused far-right groups Monday of "conniving" with the new authorities in Ukraine, as pro-Moscow forces consolidated their hold on their neighbor's Black Sea peninsula.
In a statement, the Russian Foreign Ministry condemned "lawlessness" in eastern Ukraine and accused the West of being silent over violence and detentions taking place against Russian citizens, such as one incident last week when it said masked gunmen fired on and injured peaceful protesters.
The statement came a day after German Chancellor Angela Merkel bluntly told Russian President Vladimir Putin by phone the Moscow-backed referendum on whether Crimea should join Russia is illegal and would violate Ukraine's constitution if it goes ahead on March 16.
Putin has defended breakaway moves by pro-Russian leaders in Crimea, where Russian forces have been tightening their grip on a region that has been the epicenter of a battle for influence among Moscow, Kiev and the West since Ukrainian President Viktor Yanukovych's ouster last month.
Pro-Russian forces last week pushed into the autonomous region in a bloodless siege, prompting criticism from Western nations and Ukraine's interim government.
Moscow has denounced the events that led to Yanukovych's ouster as an illegitimate coup and has refused to recognize the new Ukrainian authorities, putting the two countries on a collision course over control of Crimea, which has longstanding ties to Russia and has thousands of Russian troops stationed there.
Putin has said Russia has the right to protect Russians living in the former Soviet republic.
Ukraine's armed forces carried out training exercises to test their readiness, Kiev's Defense Ministry said. Citing televised comments made by Defense Minister Ihor Tenyukh on Sunday, it said the army however was not calling for full mobilization, as diplomacy was still the preferred method to resolve the crisis.
Singing Soviet songs
Earlier, Ukraine's Defense Ministry said a group of about 20 pro-Russian activists from the so-called Crimea self-defense squads had broken into the military hospital in the region's main administrative city, Simferopol, and thrown out its chief.
In a later statement, it said the hospital chief was back at work after negotiations but added the premises were being blockaded by the activists.
However a CNN team which traveled to the hospital found it very quiet, with no one around. A guard on duty said he had not heard or seen anything unusual and that there was no senior official to speak with as Monday was a public holiday.
In the course of the rapidly changing events of the past week, a propaganda war over Ukraine has rapidly developed as each side seeks to strengthen its stance.
Scenes of balaclava-wearing men without insignia patrolling streets or other premises have now become a familiar sight in the region, as tensions between Ukraine and Russia mount.
On Sunday in Simferopol, demonstrators waving Crimean and Russian flags clapped along to Soviet-era songs as dancers from Russia's Black Sea fleet entertained the crowd.
Because of language and history, one man at the rally told CNN, Russia and Crimea are already "brothers."
But not all Crimeans are convinced. Across town, beneath a statue of Ukraine's most celebrated poet, another crowd was much smaller and the mood much more somber.
Asked what he thought about the possibility of Crimea becoming part of Russia, one demonstrator shook his head.
"It will be very complicated because of economics, and a lot of different nations live here, not only Russians. ... Not all of the people want to be part of Russia," he said. "It's kind of a show. Putin's show."
Elsewhere, in the Crimean port of Sevastopol, another Ukrainian rally came under attack by pro-Russian gangs who whipped and beat demonstrators.
Ukrainian PM to U.S.
Washington has warned Moscow that any moves to annex Crimea would close the door to diplomacy. On Saturday, U.S. President Barack Obama rounded up world leaders to demand Russia "de-escalate the situation."
Ukrainian interim Prime Minister Arseniy Yatsenyuk will fly to the United States this week to discuss the crisis in Crimea.
On Tuesday, Yanukovych will speak from the Russian town of Rostov, Russia's state-run Itar-Tass news agency reported, citing sources close to Yanukovych.
Putin earlier this month secured permission from his parliament to use military force to protect Russian citizens in Ukraine. The move came within days after Yanukovych's flight from the country. Yanukovych was ousted after three months of protests against his decision to spurn a free trade deal with the European Union and turn toward closer ties with Moscow.
The referendum on whether the Crimean Peninsula should join Russia has become the focus of the Ukraine crisis. Yatsenyuk has called it "an illegitimate decision."
"If there is an annexation of Crimea, if there is a referendum that moves Crimea from Ukraine to Russia, we won't recognize it, nor will most of the world," U.S. deputy national security adviser Tony Blinken said on CNN's "State of the Union" on Sunday.
"So I think you'd see, if there are further steps in the direction of annexing Crimea, a very strong, coordinated international response."
-- CNN's Stephanie Halasz, Clare Sebastian, Diania Magnay, Alla Eshchenko, Claudia Rebaza, Arkady Irshenko, Azadeh Ansari, Catherine E. Shoichet and journalist Azad Safarov contributed to this report
™ & © 2014 Cable News Network, Inc., a Time Warner Company. All rights reserved.