OKLAHOMA CITY - Survivors and families of victims of the Oklahoma City bombing marked 168 seconds of silence Friday - one tick of the clock for each person who died in the bombing exactly seven years ago. <br>
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Mourners wiped away tears as church bells rang, ending the silence. Also attending were some touched by terrorism more recently, in the attack on the World Trade Center Sept. 11. <br>
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The subdued ceremony took place near an elm tree that survived the April 19, 1995 blast at the Alfred P. Murrah federal building.
