Sixty-nine doostaff have had been temporarily stripped of their Security Industry Authority (SIA) licence after a major undercover crackdown in the South-East on training malpractice.
Four London-based training providers have been banned from offering SIA licence-linked training and more than 300 certificates withdrawn, following the wide-scale investigation.
The four training providers are: Divine College; St Joseph's College of Science and Technology; ME Training, and Inter-Continental College.
All have had their approval to provide training withdrawn by their awarding bodies.
As part of Operation Nevada, the SIA made unannounced visits to the centres last November. Evidence was found of training malpractice, such as candidates being registered and awarded certificates when they had not sat the exam.
Dave Humphries, SIA's director of compliance and enforcement said: "This operation involved very successful joint working with partner organisations and has provided a model that will be used again in the future to close down training providers where there is evidence of misconduct."
Holders of an SIA door supervisor licence, based on the invalid certificates, have a 90-day period following the suspension to gain a valid qualification, or their licence will be revoked.