PARIS, March 10 (Reuters) - Unidentified gunmen have seized two Ukrainian journalists in Crimea, Reporters Without Borders said on Monday, warning that those behind attacks on the media were trying to turn the region into a "black hole for news".
"The forces controlling the Crimea are responsible for the fate of these journalists," Christophe Deloire, secretary general for the press freedom watchdog, said in a statement.
Tension in the Black Sea peninsula has been growing since pro-Russian separatists took control of the regional parliament, declaring Crimea part of the Russian Federation and announcing a referendum for March 16 to confirm this.
In little more than a week, Russian forces have taken over military installations across Crimea, home to the Russian Black Sea Fleet. Unidentified men fired in the air on Monday as they moved into a Ukrainian naval post.
"We are alarmed by the steady escalation in violations of journalists' rights in Crimea, which is turning into a lawless region controlled by armed bands whose anonymity reinforces the impunity," Deloire said.
"The frequency of deliberate attacks on journalists and the scale of the censorship suggest a desire to turn the region into a black hole for news and information."
The Paris-based watchdog said that Olena Maksymenko of Ukrainsky Tizhden (Ukranian Week) had disappeared on Sunday along with Kateryna Butko and Aleksandra Ryazantseva, two activists from the Maidan protest movement which backs the new government in Kiev.
The three women were taken after soldiers without insignia spotted a pro-Maidan tattoo on one of the women's hands at a checkpoint.
Another journalist, Crimea resident Oleksiy Byk from the Glavkom news website, saw the three women being driven away. He was arrested at the same checkpoint along with his driver Yevhen Rakhno and freelance photographer Oles Kromplyas.
Byk was released, but his two companions were still missing, Reporters Without Borders said.
"We demand that they (those controlling Crimea) provide immediate information about their location and state of health, and that they release them without delay," Deloire said.
An official who monitors media freedom for the Organisation for Security and Cooperation in Europe said after visiting Crimea last week that pro-Russian authorities there were clamping down on media that did not support them and were intimidating reporters. (Reporting By John Irish; Editing by Alistair Lyon)