A 17-year-old Afghan asylum-seeker vowing "revenge on these infidels" went on an ax-and-knife rampage on a train in southern Germany, wounding five people before being shot and killed by police -- an attack that German authorities conceded Tuesday was almost impossible to prevent.
German officials didn't identify the attacker or the victims, but Hong Kong's immigration department said among those wounded were four members of a family of five from the southern Chinese city.
The dpa news agency reported the attacker wounded the 62-year-old father, the 58-year-old mother, their adult daughter and her boyfriend. The teenage son was not hurt. The father and the boyfriend had tried to defend the other family members, dpa said.
At least one member of the Chinese family and another woman attacked outside the train were in life-threatening condition, according to Bamberg prosecutor Erik Ohlenschlager.
The Islamic State group claimed responsibility for the Monday night train attack, which came less than a week after the Bastille Day truck attack in Nice, France, also claimed by IS, in which 84 people were killed.
Bavaria's top security official Joachim Herrmann said, while the Nice attack was "clearly another dimension," in both cases the choices of weapons and targets made them "extremely difficult to prevent in any fashion."
"In one case a truck, in another an ax and knife -- those are the weapons that society cannot logically eliminate, with which any person could equip themselves, which they could put to use at virtually any location at any time of night or day," he said.
Nevertheless, he urged an increased visible police presence across the country.
Germany has not experienced the large, deadly attacks that France and Belgium have, although a string of sexual assaults and robberies on New Year's Eve in Cologne that prosecutors say were committed largely by foreigners gave rise to fears of whether the country could cope with the 1 million migrants it registered in 2015.
As the flow of migrants has slowed this year, the anti-immigrant protests have faded, but the train attack seemed likely to raise concerns again.
In a video posted by the Islamic State that purports to show the attacker, the young man calls on others to "kill these infidels in the countries that you live in."
"You can see I have lived in your own home and have planned to behead you in your own territory," the young man says in Pashto while brandishing a knife.