“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 120 kilometres 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 on 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 of the country.

Other similar and apparently unaccountable groups look to be emerging elsewhere in the region. 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.

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 thought 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 organised citizen patrols of steelworkers working alongside police to help improve security and get insurgents to vacate the buildings they had seized.

Until now, 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.

A video statement by the 47-year-old industrialist on Thursday made it clear that his loyalties are not so much with the Kiev government but with his native Donbass – territory that encompasses the Luhansk and Donetsk regions. He called for major constitutional reforms, while preserving a united Ukraine.

“This is when power goes from Kiev to the regions. This is when authorities are not appointed but elected. And this is when local authorities take responsibility for people’s real future,” he said.

Independence or absorption into Russia would spell economic catastrophe for the region, he added.

Since president Viktor Yanukovych’s ouster in February, Ukraine’s new leadership has reached out to oligarchs for help – appointing them as governors in eastern regions, where loyalties to Moscow were strong. Akhmetov, who served in Yanukovych’s Party of Regions, has avoided such engagements and his attempt to set future terms on the future of the east may cause the government to bristle.

A representative of the self-proclaimed Donetsk People’s Republic was also a party to the Akhmetov-brokered deal in Mariupol, but the insurgent group later disavowed its participation.

Instead, Donetsk People’s Republic adviser Roman Manekin said in his own video address that Akhmetov should submit to the authority of the new would-be independent entity.

“We impatiently await such a statement. Otherwise, there will be no Akhmetov in Donbass,” Manekin said.

Manekin didn’t specify how the Donetsk People’s Republic intended to enforce its demands.

German Mandrakov, who commanded the pro-Russian insurgents occupying city hall in Mariupol, said on Friday that his associates had fled, while he was “forced” to leave the building they had controlled for weeks.

“Everyone ran away,” he said, using a vulgar Russian word for cowards. “Someone is trying to sow discord among us, someone has signed something, but we will continue our fight.”

The citizen patrols organised by Metinvest now include some 100 teams consisting of two policemen and six to eight steelworkers, said police spokeswoman Yulia Lafazan.

In Washington, the White House welcomed the news that pro-Russian insurgents were leaving government building they had seized.

“We certainly welcome any indication that separatists who ... have seized buildings, who have set up roadblocks, stockpiled weapons, are vacating buildings and ceasing the kinds of activities that have only destabilised the situation in Ukraine and led to confrontations and violence,” White House spokesman Jay Carney told reporters.

The industrial labourers of eastern Ukraine have a history of mobilising to achieve political goals. In the late 1990s, hundreds of coal miners marched on Kiev demanding wage hikes in scenes that remain impressed on the memories of many Ukrainians.

In the bucolic rural village of Velyka Novosilka, a two-hour drive northwest of Mariupol, a shadowy fledgling volunteer militia calling itself the Donbass Battalion spoke of its own plans to expel pro-Russian insurgents.

The militia took over a police station on Thursday and took down the Donetsk People’s Republic tricolour flag that had been fluttering outside.

Speaking to reporters, Donbass Battalion commander Semyon Semyonchenko denied his unit had received financial aid from either the government or tycoon Ihor Kolomoisky, who media reports have linked with pro-government militias.

On Friday, around 20 battalion members were seen napping on bales of hay in a barn in Velyka Novosilka and gave no immediate indication of plans to deploy elsewhere. At least one said he was an activist in the nationalist Svoboda party, whose role in the interim government installed after Yanukovych’s ouster has led pro-Russian activists to decry what they have dubbed a “fascist junta”.

Prime Minister Yulia Tymoshenko, who is running for president in a May 25 vote, announced on Friday that 20,000 volunteers have enrolled in a resistance movement.

Speaking to supporters in the Poltava region, which lies just east of Kiev, she said that militia units and defence brigades have already been created, although she provided few specifics.

At the heart of the unrest in eastern Ukraine, however, it is the pro-Russia insurgents that are busy fortifying their territories.

Outside the strategic city of Slovyansk, an insurgent stronghold for more than a month now, armed separatists installed a new checkpoint on the eastern approaches to the city, blocking a major highway that links Kharkiv, Ukraine’s second-largest city, with the Russian city of Rostov-on-Don across the border.

In Kiev, Ukraine’s acting president, Oleksandr Turchynov, on Friday urged residents of the eastern regions to stop helping the separatists and support the central government.

“You’ve got to support the anti-terrorist operation so that we could defeat terrorists and separatists in Donetsk and Luhansk regions together,” he told parliament. “The actions of the terrorists are threatening lives and welfare of the people.”