MARIUPOL, Ukraine -- Steelworkers from plants owned by Ukraine's richest man retook government buildings from pro-Moscow insurgents, reversing the tide of rebellion and lawlessness that has gripped this industrial port and dealing a setback to anti-Kiev forces aspiring to merge with Russia.
Wearing overalls and hard hats, dozens of workers cleared away barricades of debris and tires outside the Mariupol city hall Friday, scoring early successes against the pro-Russian forces, but threatening to open a new and dangerously unpredictable cycle of confrontation.
"People are tired of war and chaos. Burglaries and marauding have to stop," said Viktor Gusak, a steelworker who joined in the effort to banish the pro-Russia militants from Mariupol, the Donetsk region's second-largest city and the site of bloody clashes last week between Ukrainian troops and the insurgents.
About 75 miles to the north, armed backers of Ukrainian unity dressed in black seized control of a police station in a village just inside the troubled Donetsk region, vowing to expel the separatists through force if necessary.
The moves, which began Thursday in Mariupol and the village of Velyka Novosilka, were a blow to the separatists who have seized control of government offices in this city and a dozen others in the east.
Other similar and apparently unaccountable groups look to be emerging elsewhere in the chaotic east. Should they make substantial incursions, it is unclear whether they will be perceived as liberators or attackers acting on behalf of a little-liked government in Kiev. The latter could precipitate civil conflict.
It is against this background that a United Nations agency Friday warned that there has been an "alarming deterioration" in the human rights situation in eastern Ukraine, where pro-Russia armed groups have engaged in killings, torture and forced disappearances.
Pro-government forces, including Ukrainian army units in eastern Ukraine, also have engaged in killings and disappearances, according to the findings of a 34-member human rights monitoring team. Some of those detained by Ukraine's security service have been transferred to Kiev, the team's report said.
Navi Pillay, the U.N. high commissioner for human rights whose office coordinates the human rights monitoring team in Ukraine, warned that the actions had created a climate of fear in the region.
"The continuing rhetoric of hatred and propaganda, coupled with killings and other acts of violence, is fueling the escalation of the crisis in Ukraine," she said in a statement.
The monitoring team's report also expressed concern about attacks on gay, lesbian and transgender people, urged the Kiev government to investigate the role of Right Sector activists in the deaths of 46 pro-Russia demonstrators in a May 2 fire in the city of Odessa, and questioned the wisdom of a new law that allows the dismissal of judges.
The team also said it had found signs that minorities, such as Tatars, have been subjected to intimidation in Crimea since Russia took control of the region in March. It said Tatars had found their movements restricted and their parliament headquarters attacked in what the U.N. called "worrying developments."
Ukrainian government forces have in recent weeks achieved only limited results in quashing the self-styled Donetsk and Luhansk "people's republics" -- armed groups that this week declared independence for their regions following contentious referendums. Polls have shown, however, that a majority of eastern Ukrainians support unity, though most are too fearful of the pro-Russian militias to say so publicly.
That has handed the initiative to expel the insurgents to forces acting independently of authorities in the capital, Kiev.
In Mariupol, billionaire Rinat Akhmetov's Metinvest holding group organized citizen patrols of steelworkers working alongside police to help improve security and get insurgents to vacate the buildings they had seized.
Until now, Mr. Akhmetov had been notable for his noncommittal stance during the turbulence that has for more than a month gripped the region that is home to his most lucrative industrial assets.
McClatchy Newspapers contributed.