1.  A fourth plane crashed in Pennsylvania as the passengers struggled to overcome the hijackers.

2.  He did not identify the fourth plane.

3.  He made no mention of the fourth plane, which crashed in a field in Pennsylvania.

4.  The fourth plane crashed in Pennsylvania, apparently after passengers tried to regain control of the plane from the hijackers.

5.  The fourth plane crashed in western Pennsylvania.

6.  The National Guard was also in place Friday in Newark, N.J., where the fourth hijacked plane originated.

7.  A fourth plane also was hijacked and appeared to be on a course for Washington.

8.  A fourth plane crashed in a field outside Pittsburgh.

9.  A fourth plane crashed in the Pennsylvania countryside after passengers struggled with their hijackers.

10.  A fourth plane was expected.