Brussels prosecutors on Monday said they had charged three more people with participating in a terrorist group after a series of raids following bomb attacks on Brussels airport and a metro train last week.

In a statement on Monday, the federal prosecutors named the three charged as Yassine A., Mohamed B. and Aboubaker O., adding they could not give further information about them at this stage.

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They also said they had released without charge a fourth man they had been questioning.

On Sunday, they had announced they were holding four people following 13 new raids in and around Brussels and Antwerp.