A 30-year old woman who was arrested in Hereford last week, was last night taken to Cambridgeshire to be questioned over the murders of Kevin Lee, who was 48, John Chapman, who was 56, and Lucasz Slaboszewki, who was 31.
It follows the arrest of a 55-year old man in Peterborough yesterday, on suspicion of assisting an offender.
The bodies of Mr Chapman and Mr Slaboszewki were found at Thorney Dyke on Wednesday 3 April. Kevin Lee's body was found four days before on Saturday 30 March in Newborough.
All three victims were stabbed. In total six people have been arrested as part of the investigation.
More top news
West Midlands weather: Dry, bright and sunny
East Midlands weather: Dry with bright spells
A rogue trader has been jailed for ripping off a Birmingham pensioner with a huge bill for work that a surveyor described as "appalling".