Then there were those unexplained nuclear explosions out over the Pacific.
There had been "a number of unexplained explosions in recent months."
Then on Monday, two Lebanese boys were killed in an unexplained explosion just north of the security zone.
That must have been it, he decided, and felt a sense of relief as the unexplained explosion slipped neatly into an understandable tactical pattern.
Its general adoption was hindered by several unexplained explosions during loading into shells.
Divers will cut away the front section of the submarine, which was destroyed on Aug. 2 by a still unexplained internal explosion.
The explosion, unexplained even today, felled sixty million trees and produced shockwaves that could be felt four hundred miles away.
The as yet unexplained explosion wiped out most of the savings Congress trimmed from the intelligence budget this year.
The unexplained explosion was the latest of a series in recent weeks in Jakarta and other cities.
On both days, Pale was rocked by unexplained explosions.