Four arrested in connection with Shirebrook murder investigation
Mr Jackson who was 55-years-old, was discovered at around 10am on Sunday 26 January at an allotment, off Prospect Drive.
A 51-year-old woman and a 44-year-old man were arrested on Thursday night (30 January).
Two further people, a 39-year-old man and a 27-year-old man, were arrested last night (31 January) and this morning (Saturday 1 February) respectively.
All of those arrested remain in police custody.
Detectives want to speak to anyone who heard a noise or a disturbance around the Prospect Drive area between 10.30pm on Saturday, January 25 and 2am the next day.
Anyone with any information that may help our enquiries is asked to contact us quoting reference number 20*049022.
They can do so by calling police on 101 or calling Crimestoppers anonymously on 0800 555 111.