1.   Agents from the Bureau of Alcohol, Tobacco and Firearms would not say whether the two bombings were related.

2.   Hamas, a radical Islamic group, claimed responsibility for the first three bombings.

3.   He declined to speculate on the type of explosives used in the two bombings.

4.   Humphries said that despite the obvious similarities in the two bombings, it was unknown whether they were committed by the same person.

5.   If the same party is responsible for the two bombings, or indeed for all three, the authorities are matching wits with a serial bomber.

6.   Investigators also released two new sketches and four photographs during their third public appeal since December for additional help in solving the three bombings.

7.   Looking at videotape, re-questioning witnesses to the various bombings, retracing their steps, but this time with a picture of Eric Rudolph?

8.   Mawn said the construction of the device that killed Mosser linked it conclusively to the other bombings, but he would not elaborate.

9.   The FBI tagged the serial bombing case UNABOM because the first two bombings were at universities, the third on an airliner.

10.   The four bombings killed two Sacramento men.