The number of prostitutes caught and arrested on the streets of Newham surged towards the end of last year.

The increase in police activity has been put down to the imminent arrival of the Olympic Games. A total of 37 arrests were made in 2011 in connection with sex work.

During November and December, a joint four-night long Metropolitan Police and Newham Council operation resulted in 21 arrests, mostly for loitering for the purpose of prostitution,

In addition, 23 police cautions were issued to street sex workers, 21 were handed warning letters, and 18 signed ‘acceptable behaviour contracts’.

The operation was launched following complaints from residents about soliciting, street drinking, littering, and public sex acts.

It comes as London Assembly member Andrew Boff revealed in Silence on Violence, his recent report into the policing of off-street sex work in London, that Newham police had closed 80 brothels in the last 18 months.

But charities have labelled this a short-term move that will only force trade onto the streets.

Miriam Merkova, from Toynbee Hall, an east London voluntary organisation, said there has been an increase in migrant sex workers.

She said: “We have found that the younger, vulnerable, migrant workers have been mixing with the experienced drug users who have been around for quite a while.

“As we are coming up to the Olympics there has been quite an effort to remove anything that people might see as antisocial behaviour, like begging and prostitution.

She added: “I do not understand the point of closing brothels because this forces people on to the streets and makes them more visible and makes it worse for the women themselves.”