DONETSK, Ukraine -- Just before the most important religious holiday of the year for both Ukrainians and Russians, the Orthodox Easter celebration today, pro-Russian militant groups have paused what had been the daily expansion of their territory in eastern Ukraine.
They have turned, instead, to consolidating political power over areas already under their control. In a string of midsize mining and industrial towns that form the core of the area under pro-Russian militant control, centered on the town of Slovyansk, pressure mounted on political dissenters and the media in ways that are commonplace in Russia, but had not been in Ukraine until now.
Internet connections went dead Saturday in Slovyansk, local news media reported, while Ukrainian television channels blinked off the air, replaced by Russian channels. Pro-Russian militants reportedly accomplished this by seizing a broadcasting tower.
Also in Slovyansk, local newspapers were not distributed after it became clear that at least some editors and reporters did not support the Russian-backed takeover of the town and intended to write critically about it.
In another sign of pro-Russian forces' consolidating politically, they announced Friday that Slovyansk's elected mayor, who had waffled in her support of their armed seizure of the town and had then mysteriously disappeared, was, in fact, in their hands and had not been seen in public because she was recovering from a medical operation.
Russia has massed troops on its side of the border, about 120 miles from Slovyansk. In a departure from earlier explanations that the troops are on a military training exercise, a spokesman for Russia's President Vladimir Putin, Dmitri Peskov, said Saturday that at least some of the troops were deployed there in response to instability in Ukraine. The government reinforced garrisons in the area "against the backdrop of what is happening in Ukraine," Mr. Peskov told Russian Channel 1 television.
With militants vowing to ignore a diplomatic agreement reached Thursday in Geneva by the United States, Russia, the European Union and Ukraine, but also halting the expansion of their territory, officials in Kiev had expressed some hope that a settlement was still possible. So the tightening of the separatists' political grip appeared to be a setback.
In Slovyansk, the pro-Russian militants who a week ago overran City Hall, first said the mayor, Neli Shtepa, would continue in her position but work in a separate building.
By midweek, this arrangement appeared to be unraveling. On Thursday, journalists who checked the new building, a dance hall, found it eerily empty except for a woman in a cloakroom, who said nobody had shown up to re-establish the old City Council. Soon enough, all pretense of allowing the elected local government to continue functioning vanished and then so did the mayor.
"She is with us," Vyachislav Ponomaryov, who has declared himself the new mayor, the "People's Mayor," announced late Friday on a loudspeaker set up in front of City Hall, masked gunmen standing behind him.
"She's in a normal condition," Mr. Ponomaryov said, according to Donbass, an online news portal covering eastern Ukraine. "It's just that yesterday she had a small crisis. She is recovering from an operation. She doesn't feel well. She signed a letter of resignation."
He said pro-Russian militants were protecting Ms. Shtepa from the central government, as Ukraine's domestic security service had opened a criminal case against her after she initially issued a statement in support of the armed men.
Armed, pro-Russian militants have seized buildings in at least 10 towns and cities since Feb. 6. Though the holiday and the agreement in Geneva appeared to have paused their efforts to purge all central government authority from the Donetsk region, it was clear all along that, for the pact to have a chance of success, the Kremlin would have to pressure the militants to loosen their grip on areas already seized.
The United States has warned that sanctions are likely if conditions of the diplomatic settlement are not met, but offered no timeline for a decision.