One video purported to show a masked Ukrainian Security Service (SBU) officer in the Western region of Ivano-Frankivsk announcing his resignation and that of several of his officers.
The video, which was released last week, claimed the unidentified man was a member of the SBU's elite Alpha special-operations unit.
"Since we swore our oath to the Ukrainian people, we decided -- our entire subunit -- to submit our resignations," the man said. "We are not going to carry out criminal orders."
Another video posted on January 30 purports to show a former officer of the Interior Ministry's special semimilitarized troops discussing widespread discontent among his former comrades facing the barricades in Kyiv.
After weeks of mass demonstrations, videos like these -- and reports that pro-European protesters in Western Ukraine met only mild resistance when they occupied government buildings in 10 regions last week -- have raised questions about the possibility of splits in the country's law-enforcement and security services.
If police begin refusing to obey the government's orders -- or if some line up with the demonstrators -- it would be a potentially decisive development in the ongoing standoff between President Viktor Yanukovych and opposition demonstrators.
Ukraine isn't quite there yet, analysts say. The thousands of Berkut specialized crowd-control officers and Interior Ministry troops have been responding to orders -- pushing back protesters, dismantling barricades, and using nonlethal force as instructed.
'Not Particularly Human Or Subtle'
According to Mark Galeotti, a professor at New York University and expert on security services in post-Soviet states, the Berkut, Ukraine's elite riot police, are almost a separate caste of people, selected and trained to emphasize obedience.
"These are very different people," he says. "On the whole they are recruited from ex-military, especially paratroopers and such like. They have a very macho and actually quite insular culture. Although they haven't always been used effectively, in the main these are tough, professional, well-trained -- if not particularly humane or subtle -- elements."
He adds that images of police being engulfed by flames from Molotov cocktails allegedly thrown by protesters make it hard for many front-line police to view the protesters as merely patriotic Ukrainians who have "taken another path."
But the longer the crisis drags on, analysts say, the higher the likelihood that the loyalty of law-enforcement troops could bend, or break.
Berkut officers, Galeotti notes, generally live and work in their communities and there is a real chance that officers could end up sympathizing with those on the other sides of the barricades.
"There is always that possibility and I think this is one of the issues as the conflict flares up more, particularly outside of Kyiv," he says. "As you start going westward, the people in Berkut are going to be west Ukrainians, they may well see their relatives or their friends, or people they were at school with, in the crowds... Even if they are willing agents of the current regime, they nonetheless emotionally have ties with the sort of strand of opinion that says Ukraine should be part of Europe, that Ukraine should not be a Russian satrapy."
In such situations, including the 1991 coup attempt against Soviet President Mikhail Gorbachev, one shouldn't expect open defections but rather "an unwillingness to get involved," Galeotti says.
As the opposition becomes increasingly entrenched and sets up, for instance, parallel governing institutions, it becomes easier for officers to step aside.
"If I was an officer in charge of a [Berkut] regiment in Lviv [in western Ukraine] and I could see that there were real signs that the tide was turning against the government, there arises that question of do you really want to be on trial in a few months' time after the regime has fallen for your actions," says Galeotti. "Again, I don't think that what we'll be seeing is necessarily defections but just simply an unwillingness to get involved."
Beefing Up Security
Perhaps mindful of this, the government appears to be taking measures to bolster its enforcers.
Deputy Interior Minister Viktor Ratushnyak said last week that the cabinet had allocated additional funding to "staff up" law enforcement agencies.
Analysts and opposition leaders fear that this means the government might add up to 45,000 additional police.
However, Hennadiy Moskal, a parliamentarian with the opposition Batkivschyna faction and a former deputy interior minister, told RFE/RL's Ukrainian Service that adding to the ranks of the Berkut is no simple matter -- since it involves fairly rigorous selection and at least six months of training.
"Consequently, raising up a new Berkut officer is not just a matter of the stroke of a pen, or of demonstrating the political will, or anything like that," he said.
If Yanukovych's government seeks to beef up security by calling on the military, it could bring about a crucial turning point, says Galeotti.
"The military has very pointedly said 'we do not have a role in these kinds of operations,'" he says. "And if then the government started to say, 'we want you to go out and support the Berkut,' I wouldn't be surprised if -- especially in the west of the country -- we began to see not necessarily units siding with the protesters, but units refusing to obey their orders. And as soon as that happens, that is really the beginning of the end for a regime."
RFE/RL's Ukrainian Service correspondent Tetyana Yarmoshchuk contributed to this report from Kyiv
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