He was armed with an automatic rifle, a pistol, a machete and a dummy suicide belt. For nine minutes, the 20-year-old gunman turned the cobbled streets of central Vienna into a war zone, firing so many shots from so many places that the authorities initially believed there were multiple attackers.
By the time the police shot him on Monday night, he had killed four people and wounded 23, shocking a country where deadly terrorist attacks are rare.
But the shooter, a 20-year-old dual citizen of Austria and North Macedonia, was well known to the authorities. Two years ago he was sentenced to prison for attempting to travel to Syria to join the Islamic State, raising questions about whether someone so firmly on the radar of Austria’s intelligence and law enforcement agencies should have been more closely watched.
Few details have been released about how the shooting unfolded or who the victims were, but the authorities have identified six locations in one neighborhood where they say shots were fired.
The dead, who have yet to be publicly identified, include three Austrians and one German, and range in age from 19 to 34, a senior government official said. Little is known about them other than one was a young man who was shot on the street, another a waitress in a bar. Among the wounded was a 28-year-old police officer.
Monday’s violence comes after recent terrorist attacks in France — including the beheading of a teacher near Paris and a knife attack at a church in Nice — that have both been linked to Islamist extremists.
Chancellor Sebastian Kurz of Austria said in an address to the nation on Tuesday that the shooting was “definitely an Islamist terrorist attack,” which he called “an attack out of hatred, hatred for our basic values.”
But Mr. Kurz, his interior minister and the mayor of Vienna all vowed that the attacker would not divide Austrian society or alter Austrians’ way of life. The chancellor warned against making assumptions about Austria’s Muslim community.
“This is no fight between Christians and Muslims, or between Austrians and migrants,” Mr. Kurz said. “This is a fight between civilization and barbarism.”
He urged citizens to remember that “our enemy is never all those belonging to a religion, our enemy is never all the people that come from a particular country” but rather “our enemy is extremists and terrorists.”
Ümit Vural, the president of the Islamic Faith Community in Austria, condemned the “cowardly, revolting attack,” calling it “an attack on our Vienna” and “an attack on all of us.”
Two Turkish-Austrians and a Palestinian who braved the gunfire to bring an older woman to safety and help save the life of the 28-year-old policeman, were celebrated in the Austrian media as heroes.
The interior minister and the police said investigators were still reconstructing the events of the previous evening, trying to determine how just one attacker, as they now believe, could have been responsible for the gunshots recorded at all six locations identified as scenes of the crime.
The first emergency calls reached the police at 8 p.m. Monday from Seitenstettengasse, a street where the city’s main synagogue is surrounded by bars in the heart of a bustling area known as the “Bermuda Triangle” because it is easy to get lost there, especially after a few drinks. There, the gunman could be seen on video firing his AK-47 at a young man in the street. He ran away, then returned to the scene, and shot the young man again with a pistol.
Another victim was found on Fleischmarkt, a street several minutes’ walk from the synagogue, and another on a nearby square beside the Franz-Josefs-Kai canal. Both had been fatally shot. The 28-year-old police officer was also shot there, surviving only because of the young men who dragged him to safety.
Around the corner, a woman waiting tables at a bar in the Ruprechtsplatz, a square named for the city’s oldest church, was shot and killed. At 8:09 p.m., police officers fatally shot the gunman in the same square, where his body lay for hours as specialists tried to gauge the danger posed by what appeared to be a belt of explosives strapped to his waist. It turned out to be fake.
Barely 24 hours after the assault, the Islamic State claimed responsibility for the attack, calling the shooter a “soldier of the caliphate,” according to a statement translated by the SITE Intelligence Group, which monitors online extremist messaging.
It was not clear from the claim whether the terrorist group had helped plan the attack or if others were involved. ISIS has used similar language before in asserting responsibility for assaults by individuals acting on their own.
Two years ago, the attacker, Kujtim Fejzulai, then 18, had planned to travel to Syria with a friend to join ISIS, his former lawyer, Nikolas Rast said. When the friend changed his mind, he went on his own. But he made it only as far as Turkey, where he was arrested and taken back to Vienna to face charges of attempted jihad and attempting to join a terrorist organization.
He was convicted and sentenced to 22 months in prison, but was released in December, after serving only about a year.
Mr. Rast, who represented Mr. Fejzulai at the trial, said that his client’s good behavior in prison — he even took part in a de-radicalization program — led to his early release.
He said that Mr. Fejzulai had appeared to show remorse. There had been no sign that his parents shared his extremist views, Mr. Rast said, adding the man’s mother had been the one to alert the authorities when her son first was missing.
“He gave the impression of a young man who was searching for who he was,” Mr. Rast said. “At no point did I have the impression that he was dangerous.”
But evidence found in the suspect’s home on Tuesday, including a stockpile of ammunition, indicated that since his release from prison he appears to have led a double life — presenting himself to the world as fully integrated into society, while embracing a radical ideology in private, Karl Nehammer, the Austrian interior minister, said in a news conference Tuesday.
Before the attack, Mr. Fejzulai posted a photograph of himself to social media, wielding a machete and a rifle with a message that “clearly indicated his sympathy for I.S.,” the minister said, using an abbreviation for the Islamic State. Investigators believe the gunman worshiped at a mosque that Austrian intelligence services suspect of promulgating extremism, an official said.
Chancellor Kurz vowed to shed light on how a man whose militant aspirations had come to the attention of the authorities in 2018 was able to slip through the net.
“The attacker tried to join the Islamic State some time ago and was arrested and convicted,” Mr. Kurz said in a telephone interview Tuesday. “He was in prison and was released early. We need to get to the bottom of why the justice system let this attacker go early.”
At least 14 people in Austria who have been linked to the suspect have been detained and are being questioned, and 18 locations are being searched, Mr. Nehammer said. The police in Switzerland said they had detained two men, ages 18 and 24, on suspicion of a connection to the attacker in Vienna, but gave no further details.
Throughout Tuesday, the cobbled streets of Vienna’s city center, normally full of tourists, government employees and other citizens, were largely empty, save for hundreds of heavily armed police officers. School attendance was optional, most stores were closed and residents were encouraged to stay home.
At several of the restaurants where the shootings took place, half-drunk glasses and untouched food still sat on tables, as if the guests had just left. Elsewhere, panicked flight was in evidence — knocked-over chairs and broken beer bottles were scattered not far from a trail of blood.
Michael Kramer, 33, who lives just yards from where the young man was killed said he had spent the night with a friend and returned only when the police blockade was lifted later Tuesday.
“You always think you are in a bubble and that nothing can happen, and then something like this happens right in front of your door,” he said, surveying the scene in disbelief.
“We often see ourselves as a blessed island where violence and terror is only known from abroad,” Chancellor Kurz said. “But the sad truth is, even if we live in a generally safe country, we don’t live in a safe world.”
Katrin Bennhold and Melissa Eddy reported from Berlin, and Christopher F. Schuetze from Vienna.