SLOVYANSK, Ukraine — The self-appointed mayor of this breakaway city in eastern Ukraine on Sunday displayed eight detained members of a European military observer mission and later released one for health reasons, but otherwise refused to discuss conditions under which the others might go free beyond mentioning a possible prisoner exchange.
In an afternoon of political theater, the de facto public authority here, Vyachislav Ponomaryov, had the detainees led into an auditorium by masked gunmen, who placed the observers in seats once used by the city’s administrators.
He then yielded the floor to the German officer leading the observers, Colonel Axel Schneider, who held a long question-and-answer session with journalists.
With erect posture, the colonel began by referring to himself and his team as “guests” under Ponomaryov’s “protection,” and said the team had suffered no violence at its captors’ hands since being seized on Friday.
“We are not prisoners of war,” he said.
In Washington on Sunday, Deputy National Security Adviser Tony Blinken said new penalties expected this week against Moscow for its actions against Ukraine will affect high technology exports to the Russian defense industry and the companies controlled by those closest to President Vladimir Putin.
Blinken says the United States and its allies will designate new sanctions against people in Putin’s inner circle and the companies they control that have ‘‘a significant impact on the Russian economy.’’ President Obama has said Russia isn’t abiding by a deal reached to ease tensions between separatists and the new government in Kiev.
During the display of prisoners in Slovyansk, Schneider noted toward the end of the conference, “I cannot go home on my free decision.”
He said the observers were performing a diplomatically accredited inspection in a rented bus when they were stopped at a checkpoint about 2 miles south of Slovyansk, the stronghold of the anti-Kiev armed militias in eastern Ukraine.
The team was held in a basement for one day and then moved on Saturday to better quarters, he said.
The observer mission included seven military officers — three from Germany and one each from Czech Republic, Denmark, Poland, and Sweden — and a German interpreter, along with five members of the Ukrainian military as escorts.
Schneider flatly rejected Ponomaryov’s claims that the observers were spies, and he dismissed allegations that the team carried ammunition and reconnaissance equipment.
“The only thing we had was a regular business-type road map, scale 1:1 million,” he said. He added that they also had “small-scale cameras.”
His team’s mission, he said several times, had diplomatic status under the so-called Vienna Document 2011 of the Organization for Security and Cooperation in Europe, which allows member nations to invite military observers from other member states to monitor internal security conditions.
“I have no overlap with any other action executed in this region,” he said. “It is forbidden.”
The detention of the team has led to intense diplomatic activity seeking their release. Russia’s representative to the security organization has publicly said that the team should be freed.
But Ponomaryov, who referred to members of the team as “prisoners of the situation,” said he has heard nothing directly from Russia.
He gave no timetable for any decisions, but insisted that the observers had been and would be treated well.
“We understand that these are officers before us,” he said. “And as we are also servicemen, we are required to abide by the officers’ code of honor.”
At another moment, Ponomaryov said the display was intended in part to reassure the observers’ families that the men were in good health.
And later in the day, he released Major Thomas Johansson, a Swedish officer with diabetes, for health reasons, said a spokeswoman for Ponomaryov. (At the end of the conference, Johansson noted that he was not ill and had access to medicine during his captivity.)
As the news conference continued, Schneider gradually expanded on his descriptions of the teams’ circumstances, making clear that its members were detainees.