Updated

Montenegro has issued an international arrest warrant for two Russians and three Serbs for their alleged involvement in a coup plot to overthrow the small Balkan country's pro-NATO government.

Montenegro's state broadcaster said Tuesday that the five are being sought for alleged "terrorist" activities that included plans to kill the country's prime minister and take over Parliament on Election Day in October.

The two Russians, reportedly members of a Russian military spy agency, allegedly tracked the movements of Montenegro's then-Prime Minister Milo Djukanovic from the territory of neighboring Serbia.

The Kremlin has denied involvement, but has actively supported local groups that oppose having Montenegro, a traditional Slavic ally, become the 29th member of the Western military alliance.

Some 20 people are in custody in Montenegro over the alleged coup scheme.