The man suspected of carrying out the fatal attack near a gay Pride celebration in Berlin tried to join Islamic State and was released from detention in May after being sentenced to prison for preparing a serious act of violence that could endanger the state, locals officials have said.

The revelations on Sunday in Berlin have spurred a heated debate in Germany, over why the suspect, a 21-year-old man who was killed in a police shootout, was freed on probation.

“How can a sentence actually be suspended on probation for someone who is identified as a threat?” Alexander Dobrindt, the interior minister, said in an interview with ARD, a public broadcaster.

The police shot and killed the suspect on Sunday night after he charged at officers with a weapon, the authorities said. That came a day after he was suspected to have killed a woman and injured 29 other people at the event. German officials have said that the attack was an act of Islamist terrorism.

The authorities have identified the suspect only as Abdul B., in keeping with German privacy laws. He had tried to join ISIS in May 2025, prosecutors said. The man had traveled to Lebanon, where he had family ties, to try to get to Syria and join the armed Islamist group. In July 2025, he was arrested in Lebanon and sentenced to three months in prison for offenses including incitement to religious and sectarian conflict.

Last November, he was arrested at the airport in Berlin after he returned to Germany from Lebanon. He was held in pretrial detention until May, when he appeared before a juvenile court and was sentenced to a year and 10 months in prison for offenses including “preparing a serious act of violence endangering the state.” He also had posted ISIS propaganda on a social media account in 2024, prosecutors said.

The sentence was suspended on probation, a special feature of German juvenile criminal law. The prosecutors said that the court considered several factors, including that he had already served nine months and that he had largely confessed and distanced himself from ISIS. The court also noted that no real threat had materialized, the prosecutors said.

The prosecutors said they had filed an appeal and requested a longer sentence.

Jim Tankersley contributed reporting from Berlin.