An undercover operation designed to find the true killer of Samantha Class came to an end after suspect Gary Allen attacked a sex worker in Scunthorpe.
Allen was jailed in 2011 for the attack, just 11 years after he was acquitted of Samantha's murder.
However, a trial has heard that the former Grimsby man confessed to an undercover officer that he had killed a sex worker and dumped her in the Humber.
An undercover officer, going under the guise of a violent criminal named "Ian", had befriended Allen as part of Operation Misty - an operation launched by Humberside Police to identify the true killer of Samantha Class and assess Allen's risk to sex workers in the area.