Home Office tried to hide surge in drunken attacks

But the Home Office omitted the figure from its report into the impact of 24-hour opening, claiming it was "not statistically significant".

Ministers have now been forced under Freedom of Information laws to reveal the missing data, which was simply replaced with a blank space when the research was published in July.

The rise of 127 per cent was recorded across 18 police regions in city centre locations or near pubs and clubs between 3am and 6am.

It covered the most serious types of violent crime, including murder, attempted murder, manslaughter and wounding.

The number of such crimes taking place throughout the day remained broadly stable.

The figures add further weight to the case against liberalisation which was supported vociferously by the Daily Mail but ignored by New Labour and then Culture Secretary Tessa Jowell, who claimed crime would fall as Britain moved to a Continental-style "cafe culture".

The report was the first to study violent trends in the year following the switch, in November 2005.

Overall, it compiled figures from 30 police forces across England and Wales.

There were 940,522 violent crimes and cases of disorder and criminal damage between the hours of 6pm to 6am in the year after the reforms, an increase of 6,300.

The most serious violent crime fell five per cent.

But within that total there was a 25 per cent rise in serious violent crime committed between 3am and 6am.

Less serious woundings rose by 26 per cent during this period.

Among the 18 police forces which looked specifically at incidents in city centres and near pubs and clubs, less serious woundings in the 3am to 6am period rose by 133 per cent.

The figure the Home Office left out plotted the same trends in the 18 regions for the most serious violent crimes.

While there was a fall of four per cent in the period between 6pm and 6am, there was a rise of 127 per cent between 3am and 6am, from 26 crimes to 59.

Shadow Home Secretary David Davis said: "We warned the Government time and again to pilot 24-hour drinking so that its consequences could be properly assessed.

"They ignored our calls and chose to unleash it on our towns and communities. This has led to a surge in violent crime and put extra pressure on our police."

Liberal Democrat culture spokesman Don Foster said the Government's attempt to suppress the research was "disgraceful".

He added: "It is completely ridiculous to try to hide something which anybody living in a town or city centre can already see and hear for themselves."

Alan Gordon, vice-chairman of the Police Federation, said: "Premises which used to close at 2am are now closing at 4am, which has simply moved the problem further into the night.

"That has had a seriously detrimental effect on resources for the police.

"alcohol-related crime is going up, and violent crime is going up."

There are now two studies showing the impact of extended opening.

Figures from the British Crime Survey show there were 1,087,000 violent attacks by drunks in the first full year of the reforms, up 64,000 on the previous year.

Before the change, the total had been falling.

This represents one attack every 30 seconds, or 3,000 a day.

A Home Office spokesman said: 'Our statisticians made a professional decision to not include the number of more serious violent crimes occurring in the specific locations returned by the 18 forces, due to the inherent variability of data based on such low numbers.

"There is an indication of some increase between the hours of 3am and 6am for each offence group, but the total offences in this time period account for only a very small proportion of the 24-hour total."

j.slack@dailymail.co.uk Comment: Page 14