11.   Debris from the first blast, investigators said, most likely penetrated an adjacent building that housed highly flammable chemicals causing a second explosion.

12.   Early Saturday, a second explosion brought down the rest of the building.

13.   He broke into a run, then heard the second explosion.

14.   It was the second pipeline explosion in as many years in Whatcom County.

15.   One theory is that a torpedo exploded, leading to the second explosion as other munitions detonated.

16.   She and some co-workers made it to a nearby hotel, where she was cowering in a corner when the second explosion occurred.

17.   She also joined a clique of Oklahomans who claim that the FBI has covered up mysterious suspects, a second explosion and advance warning of the attack.

18.   Slater said he braced himself for a second explosion since he knew there had been two airplanes that crashed into the Twin Towers in New York.

19.   The Nissan that absorbed most of the second explosion was parked next to a BMW undercover car driven by a Fulton County detective.

20.   The officials said it also appeared likely that the force of the second explosion tore apart the Kursk with the force of one to two tons of TNT.