Those three — reportedly the teenager’s father and two brothers — were released on Thursday evening and are currently not under suspicion, prosecutors told news agency dpa. They said the boy allegedly acknowledged having had contact with a bomb-building expert via the messaging app Telegram, but denied having intended to attack the synagogue.
Investigators didn't find any bomb components in a search of the teenager's home, but did seize cellphones and other materials that they will now evaluate.
Reul didn't say where the tip on the alleged threat came from.
News magazine Der Spiegel reported, without identifying sources, that it came from a foreign intelligence service. It said the teenager told someone in an online chat that he was planning an attack with explosives on a synagogue, and the probe led investigators to the 16-year-old.
Two years ago on Yom Kippur, a German right-wing extremist attacked a synagogue in the eastern German city of Halle. That attack is considered one of the worst anti-Semitic assaults in the country’s post-war history.
The attacker repeatedly tried, but failed, to force his way into the synagogue with 52 worshippers inside. He then shot and killed a 40-year-old woman in the street outside and a 20-year-old man at a nearby kebab shop as an “appropriate target” with immigrant roots.
He posted an anti-Semitic screed before carrying out the Oct. 9, 2019, attack in the eastern German city of Halle and broadcast the shooting live on a popular gaming site.
German Justice Minister Christine Lambrecht sharply condemned the foiled Hagen attack.
“It is intolerable that Jews are again exposed to such a horrible threat and that they cannot celebrate the start of their highest holiday, Yom Kippur, together," the minister said.
Geir Moulson in Berlin contributed to this report.