Earlier this week, the Met said it had received no official reports, but promised to investigate if people come forward with information.
The Healthy London Partnership, which works with the NHS, London councils and Public Health England, has warned its staff to “be very vigilant” on their way to work.
In an email, bosses said: “We are regrettably hearing reports from the Met that some NHS staff are being mugged for their passes and lanyards.
“Please be very vigilant when using your passes and showing your lanyards, and take care.”
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