More than 240 people have been arrested in a huge crackdown on people flouting licensing laws, police said.
In one of the Scotland Yard's biggest policing operations of the year, more than 3,000 officers were deployed to pubs, clubs and shops in London to curb licensing breaches.
A force spokesman said 140 cadets have also been used to perform test purchases in off-licences to identify retailers breaking laws.
Police said 248 people were arrested in the capital last night after officers visited 3,042 premises and identified 317 licensing breaches.
Police also seized 18 illegal gambling machines, and published pictures of the raid on Twitter.
Commander Mak Chishty, leading the crackdown - named Operation Condor, said: "Licensing laws are there for good reason as they help protect us from danger. Breaking them is not acceptable.
"Operation Condor is about keeping our communities safe from harm.
"In our shops and supermarkets this means people do not sell knives, harmful substances or alcohol to young people; in our pubs and clubs it means that alcohol is sold and consumed in a responsible way; on our roads it means that vehicles, such as taxis are properly licensed and safe."