Police investigating the death of a man in Hertfordshire have been abseiling down a tower block in an attempt to gain forensic evidence.
Police have been looking for forensic evidence on the building
A specialist team of officers trained in abseiling were called in by Hertfordshire Police following the death of Shumin Hussain.
The 29-year-old fell from ninth floor flat at Telford Court, St Albans just after 2200 BST on 7 September.
Mr Hussain, of Doggetts Way, St Albans, died a short time after his fall and his death was being treated as suspicious.
Flat is the 'key'
Detective chief inspector Colin Sparrow said: "Our investigations into the suspicious death of Shumin have been extensive and we are focused on maximising forensic evidence.
"The abseil team is just one example of the lengths we are willing to go to ensure that we fully investigate this tragic incident."
Mr Sparrow also appealed to anyone with information about the death to contact Hertfordshire Police.
He added: "We believe that the key to Shumin's death lies with the people who were in the flat with him shortly before he died."
Mr Shumin had been in a flat at Telford Court on Sunday evening and a number of people who were there have been questioned by police.
A 26-year-old man, a 30-year-old woman and a 25-year-old man have been bailed pending further enquiries and a 26-year-old woman has been released without charge.