Video from Met Police shows controversial drug swabs in east London
The Metropolitan Police issued a swift explanation after a controversial viral video showed officers carrying out random drug swabs in Shoreditch, east London.
The clip posted on the Met's Twitter account has been viewed more than two million times and shows officers swabbing clubbers.
An initial brief explanation said the patrol was "part of a wider operation to ensure the night time economy is a safe place for all".
But Twitter users questioned how police decided who to target and whether the process was even legal.
The backlash forced the Met to respond with a lengthy statement to clarify what officers were doing, saying it was part of a "week of action" supporting women's safety.
"The upsurge in activity included safety patrols of the night time economy, as well as tackling unlicensed minicabs, and attending schools to speak to staff and students," the statement added.
Police targeted areas which had seen a spike in incidents where women and girls were "made to feel unsafe".
"We know there is an inextricable link between Class A drugs and crime and violence on the streets of London," the statement continued.
Police said Shoreditch had been a "hotspot" for serious offences and officers agreed in advance to work with two venues to use drug swabbing.
"The use of the machine was a condition of entry... anyone who refused was not allowed entry to the venues on the night," Met Police said.
The tactic did also attract some support online with one Twitter user pointing out it could act as a "good deterrent".