The sample was recovered after the 41-year-old was murdered at a flat in Moseley Street, Digbeth, Birmingham on 9 February.
The DNA sample from the suspected killer was submitted for extensive forensic testing. It found that the suspect is a man and there’s a 99.99% probability that he is black. There was no match found on the national DNA database which senior investigators say is unusual.
Detective Inspector Jim Mahon, from the homicide team said: “The UK has one of the most efficient DNA databases in the world. To have a DNA sample from a murder suspect that does not match anyone on the database is highly unusual.
“We’re still trying to establish a motive for this violent crime and are exploring a number of reasons why Mr Zhang was killed in such awful circumstances.
“While the most likely motive is robbery, it’s clear the person who killed Zhang is a violent man and we want to catch him as soon as we can.”
Earlier this month police published CCTV of the suspect. He was described as black, in his 20s and between 5ft 4ins and 5ft 5ins tall with an average build. He was wearing dark clothing and a dark hat and mask.
Detectives also believe the killer injured his hand during the murder. A new clip released today shows the suspect walking along Barford Street, Digbeth just before the murder.
“As well as the DNA and the description, CCTV shows that the man has an unusual way of walking,” said Det Insp Mahon.
“I’d ask that anyone who thinks they may know the suspect, or someone who fits the description with an injury on the night, contacts Crimestoppers as soon as they can.
“People needn’t be afraid to come forward with names. The DNA sample we have means that we are able to quickly and easily eliminate people from our ongoing investigation”.
Alan Edwards, West Midlands Regional Manager at the charity Crimestoppers, said:
“We are reaching out to anyone who may know who was involved in this murder or has suspicions but has so far stayed silent. We absolutely guarantee that if you contact our charity and tell us what you know, you will stay 100% anonymous. Always.
“Please do the right thing and call us on 0800 555 111 or use our anonymous online form at Crimestoppers-uk.org.”
If you have any information, please contact the independent charity Crimestoppers 100% anonymously on 0800 555 111 or through their non-traceable anonymous online form at Crimestoppers-uk.org. Information passed directly to police will not qualify for a reward.
