Prison leave under scrutiny after killings

On 'radical' watchlist

But with Belgian media reporting that he was flagged as radical as recently as last year, the furlough raised concerns.

"If it were me, I would not have let him go," said Brussels security consultant Claude Moniquet, a former French agent.

Herman stabbed the policewomen, aged 45 and 53, from behind at around 10:30 am on a boulevard in the center of Belgium's third biggest city, seized their handguns and shot both. He then shot dead a 22-year-old trainee teacher who was sitting in a car before entering a high school about 100 meters away and taking two female employees hostage.

That triggered a major intervention by armed police. Pupils were moved to safety as a gunbattle broke out that sent people in the street racing for cover.

The gunman was heard shouting "Allahu Akbar" - God is greatest in Arabic - when he burst from the school shooting at police, in a video filmed by local residents. Four police officers were wounded before the attacker was finally killed.

The national crisis center, on high alert since past attacks by the Islamic State group in Paris and Brussels in the past three years, said it was monitoring events but had not raised its alert level, an indication followup attacks were not expected.

"I think it was just one individual that completely snapped and went on a killing spree," said Pieter Van Ostaeyen, a specialist on extremism who has maintained contacts with Belgians fighting in Syria. "I don't think it was an organized attack."

Reuters - Xinhua