People living in a apartment block and surrounding properties have returned home after being evacuated after reports of a chemical smell coming from one of the flats.
Police officers were called to Drill Hall in Union Street at 9.15pm on Tuesday to reports of a chemical smell coming from one of the flats.
A police cordon was in place for much of the night and yesterday as forensic examinations were carried out,
Residents were allowed to return to their homes yesterday evening (Wednesday).
A spokesperson for West Yorkshire Police said: "Officers and West Yorkshire Fire and Rescue Service attended, and a quantity of chemicals were found which are believed to be used in the production of drugs.
"A number of properties in the vicinity were evacuated while enquiries continue.
"Anyone with information is asked to contact police on 101, quoting log 2195 of 28/8."
One resident who did not want to be named described how the events unfolded on Tuesday night.
"All I know is there were people dressed a bit like firemen with devices beeping at around midnight coming in and out.
"Then at 1.30am police telling us to evacuate with no explanation other then 'to do with chemicals'.
"The residents were then taken to emergency accommodation by the council.
"The latest update is that we can return by this evening all being well."
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