The DNA fingerprints of more than 100 children aged under 10 are on the national database, even though the youngsters are under the age of criminal responsibility, it was revealed last night.

A further 883,888 records of children aged between 10 and 17, and 46 records of people aged over 90, are held.

An estimated 50,000 under-18s in England and Wales are on the database, having been arrested but never convicted or cautioned for a crime.

The figures show that a total of 108 records are held on children under the age of 10.

Last night’s disclosure, made in a written answer to Nick Clegg, the Liberal Democrat home affairs spokesman, came after a Home Office minister admitted that three quarters of the young black male population will soon be on the national DNA database.

Mr Clegg said: “The Government’s onward march towards a surveillance state has now become a headlong rush. As an increasing number of young children well under the age of criminal responsibility appear on the database, it is clear the Government sees no limits to its invasion of our privacy.

“Worse still, by harvesting the data of many people who are not even charged with an offence, let alone convicted, the fundamental principle that we are innocent until proven guilty is further undermined.

“Why should anyone be on this database if they are innocent of any wrongdoing?”

A report by the Commons Home Affairs Select Committee today gives warning of the implications of so many young black males being on the database. Baroness Scotland of Asthal, QC, a Home Office minister, had admitted that three quarters of the young black male population will soon be on the DNA database, the report said.

David Davis, the Shadow Home Secretary, said: “This is the latest in a long line of sinister developments associated with this database. It is bad enough that DNA samples from a large number of innocent adults are being added by stealth. Now we find that children, who by law cannot be held criminally responsible for a crime, are on this database. How can the Government justify this?”

Police can take a DNA sample without consent from anyone they arrest and can keep it whether the individual is charged with a crime or not, and it can be cross-referenced with criminal records held on the Police National Computer.

Officers can take a DNA sample from a child under 10 only with the consent of a parent or guardian. They can request a DNA sample to eliminate a youngster from their inquiries about a crime or confirm involvement.

The Home Office said that parents or guardians could request that a child’s details be removed from the database but the final decision was at the discretion of chief constables.

There are almost four million samples — set to rise to 4.25 million next year — on the database, which is the biggest in the world and cost more than £300 million. Just over 5 per cent of British residents have their profile on file, compared with an EU average of 1.13 per cent and 0.5 per cent in the US.

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