The News of the World has offered a £250,000 reward to catch the person responsible for the murder of five women in Ipswich.
A spokesman for the paper said the reward would be paid for information "directly resulting in the arrest and conviction of the person, or persons, responsible for the murders of the Suffolk prostitutes".
It is the second-biggest reward in newspaper history, after the £1m offered by the Daily Express in the Soham murder case in 2002.
The News of the World spokesman said: "We hope this historic reward will help in solving the series of brutal murders that has shocked the nation."
Detective chief superintendent Stewart Gull, who is leading the investigation, said he was "grateful for the support from the News of the World".
"Clearly any offer that leads to the identification of whoever is responsible for these crimes is welcome."
Newspaper rewards were criticised four years ago after the Express offered £1m and the Sun offered £150,000 for information leading directly to the capture and conviction of anyone involved in the disappearance of Holly Wells and Jessica Chapman.
Critics suggested the huge sums on offer may have played a part in people giving erroneous information to the police.
The Cambridgeshire coroner, David Morris, said the rewards had placed extra pressure on police and upset the girls' families.
Although there are many instances of big cash rewards being offered by tabloid newspapers, there have been few payouts.
The News of the World said its offer was subject to standard reward offer conditions.
"Payment will be made at the discretion of the editor, following consultation with the chief constable of Suffolk police. The editor's decision as final. In the event of more than one person qualifying, the reward may be split."
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