REUTERS/Marko Djurica Armed pro-Russian rebels stand guard outside the town hall in Mariupol, eastern Ukraine May 4, 2014.
"If I can't have him back I just want to know why they've detained him," she said, looking up the building's steel and glass facade from behind dark sunglasses.
Her son Vadim, a local politician, went missing on April 22, one of at least a dozen Ukrainians who have disappeared or been killed since rebels seized swathes of eastern Ukraine, deepening a culture of fear.
The new "people's mayor" in the rebel stronghold of Slaviansk says his men have been forced to arrest those who try to build support for the "fascist junta", shorthand for the government in Kiev. Their methods risk stirring a backlash in the future, feeding into a cycle of retribution that is pulling Ukraine apart.
Vyacheslav Ponomaryov said Sukhonos, a city council member, was detained for ties to opponents of the pro-Russian uprising in the east of Ukraine.
"He's under our watch," said Ponomaryov at a news conference from the city administration building. "Nothing bad has happened to him: he's being fed, he's clothed."
Men, blindfolded or with their hands bound with plastic wire, are led in and out of occupied buildings regularly. Ponomaryov said the measures are necessary in times of war.
"We have to make sure these people pose no threat," he said.
He tried to portray the arrests as a symmetrical response to the detentions of his "comrades" by Kiev, including pro-Russian protest leader Pavel Gubarev, who was traded for security officers earlier this week.
But with some reporting that more than 40 people have been detained in eastern Ukraine, the rebels seem more active.
Last month, they took a team of OSCE military monitors at a rebel check point, saying they were travelling with a Ukrainian spy. They were held in Slaviansk for more than a week before a Russian envoy Vladimir Lukin secured their release.
"CULTURE OF FEAR"
Western journalists have also been detained, including reporters from Internet news channels Buzzfeed and Vice News. Ukrainian journalists have been under even closer scrutiny.
Serhiy Lefter, Yury Lelyavsky and Sergei Shapoval are among those who have been reported missing, said the U.S.-based Committee to Protect Journalists.
Computer programmer Artyom Deyneha was abducted after he ran a livestream video of the state security building's takeover on April 12 for three hours, said Vice News reporter Simon Ostrovsky who was detained for three days last month.
Denis Hryshchuk and Pavel Yurov, two natives of eastern Ukraine, are also in detention in Slaviansk after stopping briefly in the city, relatives say.
The mutilated bodies of three others, including Volodymyr Rybak, a town councilor from the nearby city of Horlivka, have been found in the nearby Torez River.
MISSING SON
Galina Kovalchuk appears daily outside the state security building every day for news about her son, Vitaly, a body builder from Kiev.
On April 17, she said she accompanied her son to the train station in her home city of Vinnitsa in the west of Ukraine so he could get the train to Kiev. She then lost contact.
Days later he was filmed by Russian news outlet LifeNews with a black eye and explaining that he had come to Slaviansk to check the situation out with friends he said were from Ukraine's nationalist Right Sector group. The group, which played a central role in toppling Ukraine's Russia-friendly president Viktor Yanukovich earlier this year, has denied any involvement.
Kovalchuk, 47, has rented an apartment in the city with her husband Mikhail so they can press their campaign to free their son.
"This is miserable. Our boys are being rounded up right and left," she said. "It's arbitrary and terrifying."
Vice News reporter Ostrovsky, who described the basement of the state security (SBU) building were he was held as damp and crumbling, said all those who joined him in the cell had black eyes or other marks that suggested they had been beaten.
Detainees were allowed to use the toilet in the courtyard of the building but were kept blindfolded when they left the cell, he said. "We were kept eight people in a room and had coats that were laid out for us to sleep on," he said over the telephone.
For the rebels, the hunt for "enemies" continues.
A man named Roman was led out of the Slaviansk state security building with a towel and red duct tape that had been wrapped around his head, covering his eyes.
At a checkpoint by the building he was let go.
"I was picked up going door to door selling windows," he said thumbing through the catalogue he had shown potential clients. "I guess they just wanted to make sure I wasn't doing anything wrong," he said before walking away.
(Reporting by Thomas Grove, editing by Elizabeth Piper and Janet McBride)