Prosecutors in Brussels are investigating whether a fatal stabbing attack involving two police officers had "terrorist motives".
The incident happened on Thursday evening in the Brussels commune of Schaerbeek/Schaarbeek.
A man armed with a knife attacked two officers as they patrolled near the Gare du Nord/Brussel-Noord train station.
An officer from another patrol responded to a call for backup and shot at the suspect, who was arrested and hospitalised.
One of the police officers died from the knife wounds. Belgian media said he was stabbed in the neck. The other officer was taken to hospital for treatment.
"We have taken over the case because there is a suspicion of a terrorist motive, which will of course have to be confirmed or denied by the investigation," Eric Van Duyse, spokesman for the federal prosecutor's office, told the AFP news agency.
Belgian Interior Minister Annelies Verlinden said the event represented "terrible drama" that "breaks my heart" in a post on Twitter.
Prime Minister Alexander De Croo wrote: "Our police officers risk their lives every day to ensure the safety of our citizens. Today's drama demonstrates this once again."
A local resident told several media outlets including AFP that he heard "five-six shots" shortly after the attack.
Belgian media outlets report the attacker was shot in the legs and stomach and was taken to hospital.
According to several Belgian newspapers, the suspect had "made threats against the police" earlier in the day in a police station in another Brussels commune, without being detained.
The attack is the second knife-related incident involving police officers in Brussels this week.
On Monday, the police fired shots at a man who came at them with a knife in downtown Rue Locquenghien, near Sainte Catherine.
The man, who was said to have been drunk and disorderly, was reportedly in critical condition.
Since 2016 -- when coordinated jihadist suicide bombings left 32 people dead in Brussels airport and at a metro station, there have been several attacks against soldiers or police officers.
The latest Islamist terror attack happened in Liege in May 2018, when a radicalised petty criminal shot dead two police officers and a student. He was killed by police.
In August 2017, a 30-year-old man Muslim man attacked soldiers with a knife in the centre of Brussels, while shouting "Allah Akbar." He was also shot dead.
A year earlier, in August 2016, an Algerian man living in Belgium attacked two police officers with a machete in front of the Charleroi police station shouting "Allah Akbar", injuring them in the face and neck before being shot dead.
The Islamic State terrorist group claimed responsibility for that attack the following day.