The girl was taken into safe custody, and a bomb-squad robot searched the bag, he added.
The arrests came as officers in France swooped on a man suspected of being in the “advanced stages” of a plot to attack the country, in a raid on the outskirts of Paris.
Bouvez said police kept the area locked down and shouted at her to “get back inside” when she tried to go into the street.
U.S. Secretary of State John Kerry, speaking in a news conference Friday with Belgium Prime Minister Charles Michel, confirmed that a small number of Americans died in the Brussels attacks, but didn’t say how many.
Confirming that several FBI agents are involved in the investigation, Kerry said the “carping” about Belgium’s shortcomings “is a little bit frantic and inappropriate”.
France’s interior minister Bernard Cazeneuve said there were no links “at this stage” between the plot and the terror attacks in Brussels and in Paris in November.
Belgian authorities haven’t released details about any victims in the attack, but some information has been made public by other countries and by individuals.
The arrests come as Belgian ministers under fire for intelligence failings over Tuesday’s Islamic State-claimed suicide blasts admitted “errors” and offered to quit. “And we will not rest until we have eliminated your nihilistic beliefs and cowardice from the face of this Earth”.
Mr Geens, asked on a Belgian TV news show who was to blame for the failure to follow up on the Turkish warning, said: “It is clear it is not one single person, but it is true that we could have expected from Ankara or Istanbul a more diligent communication, we think, that perhaps could have avoided certain things”.
The attacks in Brussels, home to the European Union and North Atlantic Treaty Organisation, have heightened security concerns around the world and raised questions about EU states’ ability to respond in an effective, coordinated way to the Islamist militant threat.
Ibrahim el-Bakraoui and Najim Laachraoui – a suspected bomb maker for last November’s attack in Paris, also claimed by ISIS – were named as the two terrorists who blew themselves up at the airport. US officials said Thursday that they were on an American terrorism watch list.
One of the operations Thursday night was in the Schaerbeek neighborhood where the police earlier this week found explosives and bomb-making material used by the Brussels attackers.
Spokesman Eric van der Sypt said three of the suspects were detained “outside the door of the federal prosecutor’s office” in the centre of Brussels.
The news comes as police arrested and charged a man identified as Faycal Cheffou with terrorist murder over the Brussels terror attacks on Tuesday.
“He seemed very exhausted and he had been operated on the day before”, the official said, adding that law enforcement officials did not question him again before Tuesday.
Mr Mary, said Abdeslam “wants to explain himself in France, so it’s a good thing”.
Harrowing stories continued to emerge from survivors of the attacks, in which people of around 40 nationalities were killed or wounded.
Belgian authorities have been criticized over reports that they interrogated Abdeslam for only one hour between the time he was captured last week and Tuesday’s attacks.
Raids took place in various parts of Brussels on Thursday, including in the city center, according to reports. The agency said officials will determine later Friday whether some of those detained will remain in custody.
Interpol had a standing “red notice” for Khalid El Bakraoui, saying Belgian authorities wanted him in connection with terrorism. “What affects you, affects us”.