As many as 13 000 people have been quarantined in the Romanian capital in the wake of the confirmed presence of birds infected with avian flu there. The bird flu has been found in Bucharest's district 4, and troops and police have blocked some 40 streets. Adrian Inimaroiu, mayor of the southern district, said residents would be cut off and all businesses in the area would be closed during the quarantine period of up to three weeks. He called on residents to remain calm. Romanian authorities confirmed Sunday the deadly H5N1 bird flu virus strain in two central Romanian counties. Romania has so far confirmed 34 outbreaks of bird flu in six counties.