The relatives of those murdered by unknown perpetrators don't know whether or not they are dead these last 15-20 years.

At the time it was claimed that Wiatr had been killed by "unknown perpetrators".

Based on this evidence the episode was reclassified by the judge as homicide, but with perpetrator(s) unknown.

It was defiled by unknown perpetrators in July 1890 and is believed to have closed shortly thereafter.

"I'm not particularly happy with the unknown perpetrator," Nix admitted.

They were on guard, and their unknown perpetrator was still on the loose.

At least two times Trampedach's studio was set on fire by unknown perpetrators.

February 2, 2006 Criminal charges are filed against unknown perpetrators for wire tapping.

Dutto was killed on 21 March 1979 in a car bomb attack by an unknown perpetrator.

Some unknown perpetrator shot her in self-defense with her own gun.