BELGRADE (Reuters) - Serbian authorities on Friday detained a man sought by neighboring Montenegro in connection with an alleged coup plot during elections there last year, Serbian news agency Tanjug reported.

On election day, October 16, authorities in Montenegro arrested 20 Serbian citizens and accused them of planning armed attacks on state institutions.

Later, Montenegro’s chief prosecutor said a group of Serb and Russian nationalists had planned to assassinate then-Prime Minister Milo Djukanovic to get an opposition alliance into power.

A court spokeswoman in the city of Kragujevac in central Serbia said on Friday another suspect, identified as Predrag Bogicevic, had been arrested, the Tanjug report said.

“He in extradition detention,” she was quoted as saying.

Another man named Stanko Ristic had been banned from leaving Belgrade in connection with the case, pending the end of extradition procedure, Tanjug quoted a spokeswoman for the Higher Court in Belgrade as saying.

Serbia and Montenegro, former members of the now-defunct Yugoslavia, have an extradition treaty.

Last year, Montenegro also issued an arrest warrant for two Russian nationals. The Russian government denied involvement in the alleged plot.

Montenegrin opposition parties accused Djukanovic and his allies of fabricating the plot to extend his grip on power over the small Adriatic republic, NATO’s newest member.

In November, Montenegro’s parliament endorsed a new cabinet led by Dusko Markovic, a trusted ally of Djukanovic who remains the head of the ruling Democratic Party of Socialists.