PHOENIX — Federal investigators on Saturday began gathering debris from two news helicopters that collided while covering a police chase on live television and crashed, killing all four people aboard. The investigators plan to lay out the wreckage elsewhere to try to determine the point where the two aircraft collided Friday, National Transportation Safety Board investigator Howard Plagens said. "We're just mapping out the locations ... how things are scattered, that's our main focus," he said. Investigators said they'll need at least another day to finish going through the debris, which was sprayed across the ground and landed atop nearby...