Videos circulated on social media of a gunman running down a cobblestone street shooting and shouting. One showed a man gunning down a person outside what appeared to be a bar on the street housing the synagogue.
Condolences poured in from around the world, with top officials from the European Union, France, Norway, Greece and the United States expressing their shock at the attacks.
U.S. President Donald Trump said in a tweet that "our prayers are with the people of Vienna after yet another vile act of terrorism in Europe."
"These evil attacks against innocent people must stop. The U.S. stands with Austria, France, and all of Europe in the fight against terrorists, including radical Islamic terrorists."
Democratic presidential candidate Joe Biden condemned what he called a "horrific terrorist attack," adding, "We must all stand united against hate and violence."
Austrian minister says at least one 'Islamist terrorist' behind Vienna attack
Two men and a woman died in the attack on central Vienna on Monday night that the Austrian interior minister blamed on an Islamic State sympathiser, the only known attacker who was shot dead by police, Vienna's police chief told a news conference on Tuesday.
Austrian Interior Minister Karl Nehammer repeated calls for the public to stay at home on Tuesday in an early morning televised news conference, as he said that one attacker, heavily armed and wearing an explosive belt, was an Islamic State sympathiser.
"We experienced an attack yesterday evening from at least one Islamist terrorist," Nehammer said, adding that the attack was an attempt to weaken or divide Austria's democratic society.
Gunmen attacked six places in central Vienna on Monday evening, starting outside the main synagogue. Witnesses described the men firing into crowds in bars with automatic rifles, as many people took advantage of the last evening before a nationwide curfew was introduced because of Covid-19.
Officials confirmed late on Monday that two civilians had been killed and at least 14 others injured. Police shot and killed one assailant.
Police sealed off much of the historic centre of Vienna overnight, urging the public to shelter in place. Many sought refuge in bars and hotels, while public transport throughout the old town was shut down and police scoured the city.
Austria's capital had so far been spared the kind of deadly militant attacks that have struck Paris, London, Berlin and Brussels, among others, in recent years.
Oskar Deutsch, the head of Vienna's Jewish community, which has offices adjoining the synagogue on a narrow cobbled street dotted with bars, said on Twitter that it was not clear whether the temple or offices were targeted but that they were closed at the time.
Videos circulated on social media of a gunman running down a cobblestone street shooting and shouting. One showed a man gunning down a person outside what appeared to be a bar on the street housing the synagogue.
Condolences poured in from around the world, with top officials from the European Union, France, Norway, Greece and the United States expressing their shock at the attacks.
U.S. President Donald Trump said in a tweet that "our prayers are with the people of Vienna after yet another vile act of terrorism in Europe."
"These evil attacks against innocent people must stop. The U.S. stands with Austria, France, and all of Europe in the fight against terrorists, including radical Islamic terrorists."
Democratic presidential candidate Joe Biden condemned what he called a "horrific terrorist attack," adding, "We must all stand united against hate and violence."