Detective Inspector Warren Hines is investigating the murder of Jasbir Singh-Baines.
He was found floating in Dartmouth Park last week.
A post-mortem found that he had died from a cut to this throat.
DI Hines explains what he needs to know about Mr Singh-Baines.
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Drones use in British skies will pose a serious security risk and significant privacy concerns, intelligence experts have warned.
A sunny but chilly start. Cloud increasing with a little rain affecting northern and western areas, especially over the Derbyshire hills.
After a mainly dry, and locally chilly start, cloud will thicken, with some patchy rain possible across northern counties.