Violent crime has risen nearly 12% on the UK's railways - despite a fall in the number of other crimes, police say.
Alcohol was behind much of the violence on public transport
Many of the 9,748 attacks on passengers and staff involved alcohol, said British Transport Police.
It said it had "serious concerns" about plans to extend licensing hours as it launched its annual report.
The figures do not include the London bombings, but the force said it was facing the threat of further attacks and that it was training officers.
Overall, the number of offences British Transport Police dealt with was down 2%.
TRANSPORT CRIME 2004
There were a total of 9,748 cases of violent crime on the UK's railways
1,604 fewer crimes were reported - a fall of 1.9%
Robberies were down 20%
A third of all crime on the London Underground and Docklands Light Railway was pickpocketing
Violence rose 14% on the London Underground
Public order offences up 27%.
But it said the increase in violent crime - including a 23% rise in Wales and an 11% rise in England - was worrying. Violent incidents fell by 2% in Scotland.
British Transport Police Chief Constable Ian Johnston said there had been a noticeable increase in the reporting of alcohol related incidents and longer pub opening hours could exacerbate the problem.
He told BBC News: "We flag crimes that have an alcohol connection. So if we arrest a burglar or a robber who's drunk we flag the crime.
"And we've had about a 30% increase in that level of flagging across the force over the last year."
Mr Johnston said the "big issue" is that "longer hours means longer coverage", with the possibility of resources being overstretched if officers have to spend more of their time dealing with drunks.
It is not the first time government plans to extend licensing hours from 24 November have attracted criticism.
Judges have warned the move will lead to an increase in the number of rapes and serious assaults, while police chiefs have warned of a holiday-resort style drinking culture.
But the government said the "status quo" and not extended opening was the problem.
"Flexible opening hours will reduce the need to speed drink," said a spokesman for the Department for Culture, Media and Sport.
"It will end the double madness of people gulping two or three rounds of drinks to beat last orders and then all being thrown out onto the streets at the same time."
Rail Maritime and Transport union general secretary Bob Crow said: "It is deeply disturbing that violence on the railways is still on the increase.
"We need adequate staff on every station all the time they are open and a guard on every train, including on the Tube."
Have you experienced crime on the railways? Send us your comments.
Who are they trying to kid. The chances of finding a train still running after current closing time is extremely small. Finding a train after extended hours. no chance. So how can it make the problem worse?
R, Manchester UK
Privatised rail companies mean as few staff as possible manning stations in order that costs are kept to a minimum. It's very rare to see transport police anywhere, and only when Cardiff sees a big game, or there are terrorist attacks do you see any police. Why don't the transport police advertise for specials? People could then legitimately police their own transport as they commute to and from work. Just a suggestion.
The government are clearly trying their hardest to make the UK as difficult to live in as possible. They need to wake up to the fact that as a nation we have a large drink problem and to think that solving this problem is to extend the amount of time people can and will drink in pubs, is crazy. We are not like the rest of Europe who don't drink to get drunk. How many more people have to get hurt before drink laws are tightened and the police get the support they need and deserve?
L, Manchester, England
I've seen violent or threatening behaviour on trains many times, sometimes alcohol-fuelled, sometimes not. Currently most people look the other way and try not to get involved. The answer is simple; eject them off the train immediately. On some trains they sell alcohol. That should be stopped too.
Neil, Wrexham, Wales
As a commuter between London and Billericay for 12 years, I have seen all manner of appalling (and quite obviously drink-fuelled) behaviour on trains. Fights, over-amorous encounters, sustained vomiting, and general unruliness were all too common on Friday night trains home. The 12.51 service from Liverpool Street to Southend earned its nickname "the vomit comet" every Friday night. One thing that was rarely seen, however, was either a Police or train guard presence. Only in the last 6 months of my commute did I see either in attendance. I am glad that I now no longer have to commute by train, and pity those that do, especially late at night.
Mike Fordham, Ramsden Heath, Essex
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