The city of Brussels is in lockdown following four explosions Monday morning - two at Brussels airport and two at city Metro stations. Security has been tightened across the EU in response to the blasts. br br LIVE UPDATES: br br COURTESY: RT's RUPTLY video agency, NO RE-UPLOAD, NO REUSE - FOR LICENSING, PLEASE, CONTACT br RT LIVE br Subscribe to RT! br Like us on Facebook Follow us on Twitter Follow us on Instagram Follow us on Google+ Listen to us on Soundcloud: br RT (Russia Today) is a global news network broadcasting from Moscow and Washington studios. RT is the first news channel to break the 1 billion YouTube views benchmark.