Serbian government monitors telephones to enforce travellers' quarantine

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With more than 71,000 Serbian citizens returning to the country, primarily from Germany, Austria, Italy, and France, the government has introduced systems to ensure they obey the country's self-isolation rules. The government monitors telephone numbers, especially Italian ones, and pays special attention to communities with a large influx of people from elsewhere. 
https://advox.globalvoices.org/2020/03/30/covid-19-pandemic-adversely-affects-digital-rights-in-the-balkans/#

Source: https://mondo.rs/Info/Drustvo/a1298105/Aleksandar-Vucic-policija-telefonski-brojevi-policijski-sat-upozorenje-krecu-se.html

Writer: Advox; Mondo.rs
Publication: Global Voices; Mondo