Laughing, my colleagues at Donbas TV channel in Donetsk relive a sudden visit of half a dozen men, armed with submachine guns, in body armor and balaklavas, who came to the door and made us cut short our cigarette break well before we were half through our smokes. We had to seek shelter behind the iron door to the channel's premises. My colleagues chase away the memory with laughter: they are used to the sight of men with firearms roaming the streets of downtown Donetsk, even if those men rarely come as close to their place of work. This day, five hours earlier, another ultimatum of the so-called "Donetsk People's Republic" was delivered to the channel, demanding that the news and views be presented in a way the self-proclaimed fighters for local people's interests see fit. As a dozen times before, the channel's managers refused to oblige, backed by the entire staff. The day I came to the "Donbas" channel was different from all the previous days as it was then that "Donbas" remained the only TV channel in Donetsk still uncontrolled by rebels. The regional state TV and radio company was seized several weeks ago, then the municipal TV, and that very morning another privately owned television station saw the intrusion of people usually called separatists by journalists in Kiev and almost everywhere else in Ukraine. These same people, however, are called fighters of resistance against punitive actions of Kiev authorities by Russian media. And when Russian media appear on the site where nothing seems to signify trouble, trouble usually happens. This is why when a Donetsk colleague says: "There's a Life News crew outside the building," people at Donbas TV channel become tenser, Life News being a Russian television operation. The Donbas journalists do not pin many hopes on the patrol outside the door: there are four people in combat fatigues representing opponents of central authorities, and two regular police officers. As is well known throughout Ukraine, police often surrender arms when confronted by rebels, so chances that the guards will protect the TV channel from attack are fifty-fifty at best. Meanwhile, I go on air as a guest for a phone-in talk show, and then - cigarette, and then commotion, and then the armed men in balaklavas withdraw. It turns they were a rapid deployment force from a private security structure of billionaire Rinat Akhmetov, the owner the Donbas TV, and came here without warning when alerted about the possible attack on the medium. Whatever his political inclinations are, Ukraine's wealthiest person obviously is ready to protect his interests, weapons in arms, albeit not his own arms - but he seems to have enough weapons. On the day of the so-called referendum on federalisation in Donetsk Region Rinat Akhmetov calls upon central government to stop the anti-terrorist operation in the East and announces formation of militia from among workers of metallurgic plants owned by him. A smart move to legalize his private army? Somehow I am now more relaxed about safety of my colleagues at Donbas TV channel. But less sure about security and territorial integrity of Ukraine. Andriy Kulykov, Public Radio Ukraine, Donetsk.