There were "no indications" that the teenage gunman who killed nine people and then himself at a mall in the German city of Munich had links to ISIS or any other terror group, police said Saturday.
Seven of the nine who were killed during the Friday evening rampage were themselves teens, officials announced. Three were female. The attack also injured 27, police said at a news conference.
The gunman shot himself in the head after police made contact with him, authorities said. German media have identified the suspect as David S.
Searches revealed that the 18-year-old who was born and raised in the Bavarian capital had "looked intensively" at the subject of "shooting rampages," Police Chief Hubertus Andrae told reporters.
A book entitled "Rampage in Head: Why Students Kill" was found among the suspect's belongings, officials said.
"There is no indication that there is a link to ISIS," Andrae said.
That the shooting was carried out on the fifth anniversary of white supremacist Anders Breivik's deadly rampage in Norway indicated that the attack may have been motivated by far-right ideology, he said.
"The connection is apparent," Andrae added.
It also appeared that the attacker had hacked a young woman's Facebook account and posted a message to lure people to the mall for a free meal, said police investigator Robert Heimberger.
Munich woke up to a state of emergency the day after the shooting spree, with police scouring the city for clues to explain why the teen opened fire at a McDonald's attached to the Olympia Einkaufszentrum shopping center Friday night.
Overnight, police searched the suspect's home, which he shared with his parents and a brother, Andrae said. Family members had not been questioned because they were "too affected," he added.
Earlier, the police chief had told a news conference that it was too early to label it an act of terrorism, although authorities had used the term earlier to describe the nature of their operation, which included calling in the elite GSG9 special operations force.
On Saturday, flags throughout the country flew at half-staff while Germany's security cabinet got set to meet in Berlin at 12:30 p.m. local time (6:30 a.m. ET).
German Interior Minister Thomas de Maizière cut short a trip to the U.S. to attend the gathering chaired by Chancellor Angela Merkel.
De Maizière said at a news conference Saturday that he understands that the nation remains "shaken" after recent attacks in public spaces in Europe.
"For many hours we feared that we might be dealing with an even bigger attack," he said, "especially as there were other reports of shootings around the town, which then turned out to be false."
Munich Mayor Dieter Reiter canceled all events and festivities in the city, saying in a tweet: "Today is a day of mourning, not celebration."
As the attack unfolded Friday, authorities locked down the Bavarian capital, shutting public transportation and warning residents to stay away from public places.
A cellphone video posted online showed the suspected attacker standing on a rooftop parking lot yelling back at a person filming.
"I'm German," the suspected attacker said before eventually firing shots. Police said they believed the video is genuine.
Around 2,300 police in Germany and neighboring Austria were initially called to respond to the rampage, which happened less than a week after a 17-year-old Afghan asylum-seeker wounded five people in an axe-and-knife rampage that started on a regional train near the Bavarian city of Wuerzburg.
ISIS claimed responsibility for the train attack, but authorities have said the teen — who was shot and killed by police — likely acted alone.