Expressing shock, disbelief and something bad

Shock:

• I was shocked to hear…
• The news came as a complete shock.
• We're all in complete shock.
• Everyone's reeling from the shock of…
• It happened out of the blue.
• Who could have predicted it?
• I (just) can't get over …
• We were completely taken aback by…
• I was just stunned by…
  

Disbelief:

• I just can't believe…
• It's unbelievable.
• I just can't imagine…
• Words can't describe… (How I feel about / the terrible devastation etc)
• There's no way it could have happened.
  

Saying how bad something is:

• It's so awful.
• It's terrible.
• What a terrible news.
• It's a tragedy.
• It's a catastrophe.
• This is the worst thing that could have happened.