The Islamic State group on Sunday claimed responsibility for a weekend machete attack that wounded two policewomen in the Belgian city of Charleroi, calling it an act of reprisal carried out by one of its "soldiers."
Belgian prosecutors identified the machete-wielding assailant as a 33-year-old Algerian known to police for criminal offenses, but not for extremist acts.
The attack on Saturday afternoon is being treated as a terrorist incident, notably because the man shouted "Allahu akbar!" -- Arabic for "God is great" -- as he slashed at the officers outside Charleroi's main police station, Prime Minister Charles Michel said.
The assailant, shot by a third officer, died later in a hospital. A statement by the IS-affiliated Aamaq News Agency, posted Sunday on an IS-linked Twitter account, said the attack on the policewomen was in response to the "Crusader coalition's" military campaign against IS and its self-declared caliphate in Iraq and Syria.
Belgium, a longtime U.S. ally, is a member of the American-led coalition combating IS, and has supplied warplanes to participate in anti-IS operations.
The Belgian Federal Prosecutor's Office said the attacker, who it identified only as K.B., had lived in Belgium since 2012.
"Since there are indications that the attack may have been inspired by a terrorist motive, the federal prosecutor's office decided to take over the investigation from the district prosecutor's office of Charleroi," the federal office said in a statement.
The office said two police searches were carried out overnight in the southern Belgian city, but that no further information about the investigation would be made public.
Both policewomen were "severely injured in the face and neck" in the attack, the federal prosecutors' statement said. Michel said the prosecutors had opened an official investigation into what they deemed a case of "attempted terrorist murder."
The prime minister spoke to reporters following an emergency meeting with top Belgian law enforcement officials Sunday morning. Michel cut short his vacation in the south of France to hurry back to Brussels following the Charleroi attack, which had some police unions clamoring for greater protection for police officers and installations.
"We must keep a cool head," Michel said. "We must avoid panic, of course -- not give in to terror. That's the trap that has been set for us."
Belgium has been on high alert since the March 22 suicide bombings claimed by Islamic State extremists that killed 32 people in Brussels. Many of the perpetrators of the Nov. 13 carnage in Paris that killed 130 people were also residents of Belgium. That attack was also claimed by IS.
"We know we must be constantly, constantly vigilant," Michel said.
Defense Minister Steven Vandeput said the government's Crisis Center would meet to determine if additional measures should be taken to protect police buildings and staff.
On Sunday, Charleroi police posted a request on their Twitter account asking reporters not to divulge officers' identities.
"We are targets," Charleroi police explained.
Prosecutors said K.B. was carrying a backpack at the time of the attack, but that a bomb squad search found no explosives or other weapons inside.