Shots were reportedly fired near a synagogue in Vienna.
Several people are said to be injured and a large police force has been dispatched.
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On Twitter, the police in the Austrian capital indicated that a
"major police operation"
was underway in the city center of Vienna following
"several exchanges of fire".
According to the police,
"three people were injured
". "Please avoid all public places in the city or public transport and do not share videos or photos," Vienna police said.