I'm guessing suicide bombers, instantly thought it might be and reports now suggesting the airport attack at least was.
Guys - Lets not make this reddit or youtube. If you don't have any news to add, stay the fuck out.
I really don't feel like I need to baby sit the posters AND the people reporting their posts.
Seems like this is one of the hashtags to follow:
https://twitter.com/hashtag/Zaventem?src=hash
And this might be the official twitter acct to follow:
https://twitter.com/CrisiscenterBE