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WhatsApp, Viber blocked during Montenegro election day

Montenegrin officials blocked popular messaging services WhatsApp and Viber during the country's parliamentary election, a ban that drew allegations of interference from opposition politicians and concern from European election watchers Monday.

"Blocking such apps is unthinkable in any normal country," said opposition party leader Ranko Krivokapic, who previously monitored voting for the Organization for Security and Cooperation in Europe. "I have never heard of that happening anywhere ever in an election."

Authorities said they blocked Viber and WhatsApp for several hours during Sunday's inconclusive election because "unlawful marketing" was...