Molenbeek

Salah Abdeslam, chief suspect in last year's November 13 terrorist attacks in Paris, had planned to blow himself up at Stade de France but changed his mind.

Abdeslam admitted this during interrogation by Belgian investigators on Saturday, a day after his detention in the Brussels neigbourhood of Molenbeek on Friday.

Belgian authorities raised the terror alert in the region of Brussels to the highest possible level fearing a "very serious" and "imminent" threat.

The underground will remain closed until at least Sunday and the citizens have been warned to avoid places of mass gatherings, including shopping centers and concerts.

Bulgaria advised on Tuesday its citizens travelling to Belgium or staying there to be vigilant regarding potential terrorist attacks.