The US Secretary of State is is travelling to Brussels, Belgium, to formally express U.S. condolences for the loss of life in Tuesday's terrorist attacks.
As many as 12 US citizens were caught up in the attacks, with many still unaccounted for.
John Kerry is expected to meet with Belgian and European Union officials on Friday.
US State department spokesperson Mark Toner said identifying the injured was an ongoing process
IN:We're trying..'
OUT: '...the families'
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US state department Spokesperson Mark Toner said it was not up to the US to grade how effective Europe's anti-terror measures have been...
IN: There's always..'
OUT: ...security
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