(QHA) -

A pro-Russian rebel leader in Ukraine’s Slovyansk says he is holding captive 4 OSCE observers.

The Organization for Security and Cooperation in Europe (OSCE) said on Monday that it had lost contact with one of its monitoring teams in the Donetsk region.

On Thursday, the self-proclaimed mayor of Slovyansk, Vyacheslav Ponomarev said the four observers are being held captive, and are in good condition, the AP reported. He did not specify any particular demands for their release.

This is the second such incident, after 7 OSCE observers were kidnapped last month in Slovyansk. They were released several days later.