Terror suspects are to be excluded from plans to delete DNA profiles from the national database after six years, under government proposals published yesterday.

Those arrested on suspicion of terror offences but released without charge could have their DNA profile kept on the national database indefinitely.

Under the plans the samples of under-18s arrested on suspicion of involvement in terrorism could be on the database for the rest of their lives.

A senior police officer would review the cases of terror suspects every two years and make recommendations on whether the samples should be removed.

Alan Campbell, a Home Office Minister, said that the tough approach was justified. He said: “The reality is that many investigations of counter terrorism actually take a very long time indeed. They have to be treated differently to other offences.”

Home Office officials said that the number of DNA samples on the database relating to people arrested for a terror offence but not subsequently charged runs in to the hundreds.

Under the plans the Government has watered down a number of proposals outlined in a consultation document earlier this year.

Children arrested for a minor crime who are not charged or are cleared in court will have their sample on the database for three years rather than the six years previously proposed.

Adults arrested but cleared of violent and sexual crimes will have their DNA removed after six years instead of twelve as had been planned.

But the Home Office is pressing ahead with plans to keep the DNA of adults arrested and cleared over less serious crimes for six years.

The DNA of 17 and 18-year-olds arrested over violent and sexual offences will also remain for six years even if they are not charged or are cleared at a trial.

Under 18s convicted of a minor crime will have their DNA stored for five years and indefinitely on conviction of a second crime.

The plans follow a European Court ruling which said that the current policy of retaining indefinitely the DNA samples of everyone arrested, including those not subsequently charged or cleared at a trial, was disproportionate.

Mr Campbell said: “We consider that this package is a proportionate and effective response to the judgement of the European Court balancing the right of unconvicted individuals to have their DNA samples and fingerprints removed from the database with the right of the public to be protected from the fear and threat of crime.”

The Home Office estimates that there are up to one million samples of unconvicted individuals on the database, the largest of its kind in the world.

Times Recommends

• Margot Fonteyn: In her footsteps
• Forget beautiful people, let's have wonky Brits
• Fundamentalist brew: faith and power