At the time of writing the death toll in the atrocity was 28 - with suspect Adam Lanza apparently killing 20 children and six adults at an elementary school in Connecticut.
Paramount Pictures issued a statement which read: "Due to the terrible tragedy in Newtown, Connecticut, and out of honour and respect for the families of the victims whose lives were senselessly taken, we are postponing tomorrow's Pittsburgh premiere of Jack Reacher.
"Our hearts go out to all those who lost loved ones."
The movie had its London premiere in the week and opens on 21 December in the US and 26 December in the UK.
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