Criminal gangs have infiltrated British society, practising a variety of illegal activities from paedophilia to drug dealing, a police report says.
Drug trafficking is identified as a serious problem
Gangs ranging from traditional British "firms" to the Italian Mafia continue to pose a high threat and touch every community, according to the National Criminal Intelligence Service (NCIS).
The report warns drug trafficking "represents the greatest threat from serious and organised criminals".
It also says the number of websites showing illegal images of child abuse has increased, adding that online child sex offenders are becoming much more cunning in their attempts to avoid detection.
The fourth annual NCIS assessment of the threat posed in the UK by serious and organised crime analyses current and emerging threats from crime gangs and looks at how they are likely to develop.
It also looks at the chain of command within the gangs.
It says gangs are targeting the illegal immigration trade, and warns that drug dealers are "aggressively promoting" heroin and crack cocaine use in the UK.
Peter Hampson, director general of NCIS, said: "The impact of serious and
organised crime is felt by everyone in the UK.
"The trades in drugs, people and illicit goods, the related crime and
violence, and the corruption of people from all walks of life cause damage to
families, communities and society in general.
"Serious and organised criminals are determined, ruthless and
quick to adapt to threats and opportunities.
"We must show them that we are more
determined, more ruthless and quicker on our feet, and the key to this is good
The Internet Watch Foundation, which alerts the police to websites containing images of child abuse, saw a 64% rise in the number of reports of illegal sites it received in 2002 compared with 2003.
Most are based in the United States - but the number in Russia also more than doubled from 286 to 706.
And the sites that are reported are just the tip of the iceberg, according to police.
Child porn offences on the net carry tough custodial sentences.
To avoid detection, members of online child sex networks attack with viruses the computers of those who have put others at risk by the unauthorised passing on of illegal images.
Paedophiles are naturally suspicious of newcomers into their social circle and, like many criminal groups operating in cyberspace, are skilled at counter-surveillance, the report found.
They also debrief people who have been arrested and try to monitor the methods employed by law enforcers.
Home Office Minister Hazel Blears said the government was due to spend millions
of pounds to tackle the serious criminal activity highlighted in the NCIS report, published on Thursday.
The new Proceeds of Crime Act, under which an Assets Recovery Agency is tasked with confiscating the profits of crime, provided a "major new weapon against serious criminals who profit from crime", she added.
A multi-agency taskforce of police, immigration and intelligence agencies had reduced gangs' profits by disrupting organised immigration crime.
Ms Blears said a new offence of "grooming" in the Sexual Offences Bill and a maximum
penalty for possession of child pornography, along with guidance for parents and
children, was helping to protect children on the internet.