Jan Jambon

A string of explosions rocked Brussels airport and a city metro station on March 22, killing at least 13 people, according to media reports, as Belgium raised its terror threat to the maximum level.

Authorities in most capitals of the world fear of terrorist attacks during New Year’s Eve celebrations and have increased police presence in the cities’ streets to prevent any attack.

Belgium widened its search on Nov. 22 for armed Islamist extremists whose presence has put Brussels on maximum alert, with officials saying more than one militant was at large in the city.

The alert has closed the capital's metro system, although a senior minister said it was likely to reopen on Nov. 23. 

Belgium on Aug. 31 unveiled plans for a controversial system to collect data on all airline passengers, as well as international train and ferry travellers, in the wake of a foiled attack on a train running between Belgium and Paris.