But the word that's spread the next day says that the unknown killer started the fatal fight.

The report must label the escaping man as an unknown killer.

They were the messages which had come from the unknown killer.

In the novel, the unknown killer of Edmund's brother is not given a made up name.

Some unknown killer just bought me a brand-new beautiful life.

The Shadow's agent knew that a heavy search was due for an unknown killer.

Young female students are being targeted by an unknown serial killer.

If there did still remain some secret, unknown killer, no sight or sound of him remained.

That this unknown killer had nerve was an apparent fact.

"I believe that one of your own teachers, a year or two ago, was strangled by an unknown killer."