Drug users appear to have taken cocaine in Norwich's bus station toilets, but five other places in the city tested by this newspaper were found to be clean.
We used industry-standard cocaine detection wipes to test for the Class A drug in the toilets of six public buildings in the city centre.
This included the male and female cubicles in Norwich Magistrates' Court, the bus station, railway station, Norwich Cathedral, the Forum and the market toilets.
The wipes turn blue when they come into contact with cocaine traces and of all the toilets tested the only positive result was the city's bus station off Surrey Street.
The positive result was found when we wiped the toilet roll holders in the two male cubicles, both of which turned a faint blue.
The intensity of the colour depends on the amount of cocaine found.
We carried out the test on Monday afternoon, wiping across the top of hand dryers, sinks, toilet roll and soap dispensers, toilet seats and other flat surfaces.
Zoom Testing, where the wipes were purchased from, states: "These are of the same type used by the police in the UK and also by local authority licensing officers who use them inside pub, clubs and bars around the country."
In the remainder of the toilets - and also in the baby changing rooms - the wipes did not produce any noticeable results.
Konectbus, which manages the bus station, did not respond to a request for comment.
The bus station building - where the toilets are located - is open between 7am-6.30pm on weekdays and Saturday and 9am-5pm on Sunday and public holidays, meaning the drugs are being taken during the day.
According to the crime map on police.uk, there have been no reports of drug crime at the bus station this year or in 2018.
However, there were 24 incidents logged in 2018 in nearby areas, including the nearby student accommodation, St Stephens Street, Chapelfield and Queens Road car park. So far this year, there have been 15 reports of drug offences in that part of the city centre.
In July 2017, this newspaper reported on peoples' concerns over drug-taking in the city after a group of men were filmed snorting drugs off a wall in New Mills Yard. Norfolk police have declined to comment.
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