Three people, including one attacker, died after multiple gunmen opened fire across central Vienna on Monday, and at least one attacker remained on the run after what Chancellor Sebastian Kurz described as a "repulsive terrorist attack."

One of the victims was killed at the scene of the shootings while a second died later in hospital from her wounds, Mayor Michael Ludwig said.

At least 15 others were injured in the shootings. A police officer is among the seriously injured, the Vienna Police (LPD Wien) wrote on Twitter.

There were six different shooting locations and the attackers used long guns, it added.

Interior Minister Karl Nehammer warned people to stay away from the center of the city, as officials said border checks were being reinforced and that children would not be required to attend school on Tuesday.

Several "heavily armed and dangerous" attackers were still on the loose as police shut down and sealed off large parts of central Vienna in a manhunt, Interior Minister Karl Nehammer said, adding the incident appeared to be a terrorist attack.

All six locations were in the immediate vicinity of the street housing the central synagogue, said Nehammer, adding that border checks are reinforced and children are not required to go to school on Tuesday.

First gunshots were fired at around 8:00 p.m. local time in the city's centrally-located first district. The shooting began just hours before Austria was to re-impose a coronavirus lockdown to try to slow the spread of COVID-19, and bars and restaurants played host to people enjoying a final night of relative freedom.

Jewish community leader Oskar Deutsch said on Twitter it was not clear whether the Vienna synagogue and adjoining offices had been the target and said they were closed at the time.

Frequent sirens and helicopters could be heard in the city center as emergency services responded to the attack.

Austrian Chancellor Sebastian Kurz condemned the "hideous terrorist attack" in the Austrian capital, vowing to "take decisive action" against the perpetrators.

"We are currently going through difficult times in our republic," Kurz wrote on Twitter. "We will never allow ourselves to be intimidated by terrorism and will fight these attacks resolutely by all means."

EU leaders, countries condemn Vienna shootings

European Council President Charles Michel and European Commission President Ursula von der Leyen as well as leaders of European countries condemned the shooting attacks in Vienna late on Monday.

"Europe strongly condemns this cowardly act that violates life and our human values," said Michel on Twitter. "We stand with Austria," he stressed.

Von der Leyen said she was shocked and saddened by the brutal attack that took place in Vienna. "Europe stands in full solidarity with Austria. We are stronger than hatred and terror."

French President Emmanuel Macron said on Monday evening that the French share the shock and sorrow of the Austrian people following the shootings, pledging that "our enemies must know who they are dealing with. We will not give in."

The German Foreign Office tweeted late Monday, "Even we don't know the full extent of the terror yet, our thoughts are with the injured and victims at this difficult time. We will not give way to hatred which is aimed at dividing our societies."

In London, British Prime Minister Johnson said the "UK's thoughts are with the people of Austria – we stand united with you against terror."

Italian Prime Minister Giuseppe Conte tweeted: "There is no room for hatred and violence in our common European home."

Dutch Prime Minister Mark Rutte called the shooting "a heinous act" and expressed "solidarity" with Austria.

Past attacks in Austria

In 1981, two people were killed and 18 injured during an attack by two Palestinians at the same Vienna synagogue. In 1985, a Palestinian extremist group killed three civilians in an attack at the airport.

In recent years, Austria has been spared the sort of large-scale attacks seen in Paris, Berlin and London.

In August, authorities arrested a 31-year-old Syrian refugee suspected of trying to attack a Jewish community leader in the country's second-largest city Graz. The leader was unhurt.

(With input from agencies)