WASHINGTON - The Obama administration on Thursday expressed new concerns about rising violence in eastern Ukraine, including the downing of a military helicopter by pro-Russian rebels battling the government.
The White House and State Department both said a de-escalation of the crisis was imperative and called on Russia to exert pressure on the separatists to get them to end the fighting and release a group of international monitors who have been detained in eastern Ukraine since earlier this week.
"We are disturbed by on the ongoing violence in eastern Ukraine," White House spokesman Jay Carney said. While the U.S. has not been able to verify what happened to the helicopter, he said, "We are concerned that this indicates separatists continue to have access to advanced weaponry and other assistance from the outside."
Ukraine's acting president said earlier Thursday that 12 troops died when rebels shot down a military helicopter in Slovyansk using a portable air defense missile.
Even before the incident, Secretary of State John Kerry spoke to his Russian counterpart, Sergey Lavrov, on Wednesday to reiterate U.S. concerns about the deteriorating situation in Ukraine, the State Department said.
Kerry raised with Lavrov reports of Chechen fighters crossing into Ukraine to join the separatists, spokeswoman Jen Psaki said.
Kerry "pressed Foreign Minister Lavrov to end all support for separatists, denounce their actions and call on them to lay down their arms," she said.
"Our broad view, as you know, is that de-escalation is the proper path forward," Psaki added, although she said she was not aware of concerns that Ukrainian security forces were using disproportionate means to quell the fighting as some Russians have alleged.
Carney and Psaki also said it was unacceptable that insurgents have detained four observers from the Organization for Security and Cooperation in Europe. They demanded their immediate release.