The murder appeared to be a thrill killing as the pair did not know Lamb.
Serial murders also appear to have increased over the past 30 years.
The killer made the murder appear to be performance art.
Mr Hill said the murder still appeared to be motiveless.
But they said the murders appeared to be acts of simple revenge unrelated to drugs.
In the first case, the murder appeared to have been unplanned, and the killer panicked.
The first murder appears to be accidental, or consciously unplanned.
The murder, appeared to have been carefully planned and executed.
In Auschwitz, however, creation is accomplished, since murder, at reverse speed, appears to be the giving of life.
A murder of crows appeared from the north, fighting the wind.