A man wielding a machete and shouting "Allahu Akbar" attacked two female police officers in in the Belgian city of Charleroi, wounding one of them seriously, The assailant was shot dead at the scene by a third officer.
The police officer who was wounded is now reported to be out of immediate danger.
The man took out the machete just before officers tried to search him at a checkpoint outside the main police headquarters in Charleroi.
"Initial indications clearly point towards terrorism," Belgian Prime Minister Charles Michel told reporters.
President Michel returned from a holiday to discuss the security situation with police officers.
This summer, terrorist attacks have struck France and Germany and the Islamic State has called on its supporters to carry out "lone-wolf" attacks against Western countries without waiting for coordination with central command or travelling to the Islamic State.