A man briefly held a group of people hostage in a supermarket in a Brussels suburb before surrendering to police. Nobody was injured and authorities say there was no indication of any terrorist motive.
Brussels justice spokeswoman Ine Van Wymersch said Tuesday night, "we have no indications that this would be a terror action."
Claude Inno, who was briefly taken hostage, called the man "a crazy person" who held several people before he started negotiating on the phone.
Police could not immediately say what weapon the man was carrying.
Brussels has been on high alert since 32 people were killed March 22 in suicide bombing attacks on the city's airport and subway.
On March 22, 2016, 16 people were killed in two suicide bombings as bombs ripped through check-in counters at Brussels Airport. The Islamic State group claimed responsibility for the attack. A subsequent explosion at a Brussels subway station killed 16 more people.
Meanwhile, Belgium on Tuesday charged four people with involvement in terrorism after 15 early morning raids in the northern cities of Ghent, Antwerp and Deinze.
Some of them, who grew up in central Brussels and were known to the authorities, also took part in the November Paris attacks, which claimed 130 lives and left hundreds injured.
Belgium has been on its second highest terror alert since the Paris and Brussels attacks.
There has been a series of incidents since March despite a much increased security presence on the streets, the latest early this month when two police offers were stabbed in the Schaerbeek area of Brussels.
(With AP inputs)