A bouncer was found working without a legally-required licence during checks carried out in Maidenhead on Tuesday last week.
In a joint operation between Thames Valley Police, the Security Industry Authority (SIA) and the Royal Borough, 20 security workers were checked across seven venues in the town, including pubs and off-licences.
During the investigation one bouncer for a pub was found to have a revoked SIA licence, while a bar owner did not hold the correct SIA licence.
Enquiries are ongoing.
Licensing offences can lead to up to six months imprisonment and/or a fine of up to £5,000.
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