A survey of middle school children found that one of their biggest fears was those late-breaking news reports without an adult there to interpret it for them. So don't assume that your older child will not be affected by the news.
Research also shows that younger children do not have the cognitive understanding to recognize that the televised images they are seeing or hearing may be repeats. Instead, they assume the event they are watching is happening live. For instance, each time young children saw the televised images of the planes hitting the World Trade Center towers they assumed the event was live. Images of a tragedy can exacerbate a child's existing anxiety and actually increases aggression in some kids. Monitor the news.