Executed in cold blood, aged 7

Shot dead by a callous killer, Toni-Ann Byfield is the youngest victim yet of Britain's gang warfare

Saturday was a big day. Toni-Ann Byfield was going with her father to buy her new school uniform. She had just arrived from Jamaica, and was looking forward to a fresh start in London.

Her family situation was difficult, as one officer said with some understatement. She was a ward of court, her mother back in the Caribbean, whereabouts unknown. She was staying with her dad, Bertram Byfield, 41, just for the weekend.

A family friend said yesterday: "I saw them both, buying her school uniform. She was very bright and cheerful. She seemed very happy.''

A few hours later, soon after midnight, Toni-Ann was dead, executed. Her age? Just seven.

She was with her father, a convicted drug dealer, in his bedsit in Kensal Green, north London, when his assailant came calling. As he fired several shots into Mr Byfield's body, the little girl ran away, screaming. The gunman had a decision. Let her live, and risk identification. Or make sure that she could not help the police. So he shot her, once, in the back, as neighbours heard her scream her last, and made good his escape.

And so Toni-Ann enters the record books, believed to be the youngest victim of Britain's burgeoning gang wars and the country's gun culture epidemic. And what makes it all the more shocking is that she was no accidental victim, a bystander caught up in a drive-by shooting.

She was picked off.

Last night police arrested a 23-year-old man who is being questioned at a north London police station.

There was a quaver in Detective Chief Superintendent John Coles' voice as he spoke about his inquiry yesterday. There was, though, no mincing of his words: "It is without doubt the most evil and despicable crime I have come across in all my service.'' Mr Coles is head of Scotland Yard's Operation Trident, which investigates black-on-black gun crime. Detectives believe the murder has the hallmarks of being Yardie-related, though they are also investigating Mr Byfield's complicated domestic arrangements.

He certainly had his enemies. He had served nine years in jail for dealing in crack cocaine, and had lived in the bedsit since his release two years ago. On 29 January last year, Byfield, also known as Tony, was shot six times as he walked near his home. That time, he survived, and Robert Grant, 23, who was accused of the attempted murder, was cleared at the Old Bailey last October.

Neighbours at the scruffy Georgian building recalled a larger-than-life character with short dreadlocks and a string of girlfriends and children. He irritated them by constantly parking on the pavement.

His two-room home was often full, and Toni-Ann knew to be quiet when the visitors came, round-the-clock. So "complex" was her domestic life, as Det Ch Supt Coles put it, that Interpol was called in to try to locate her mother. Police struggled to find relatives to identify the bodies. They eventually made contact with some living in Birmingham.

Just down the road, a smart gastro-pub packed with young, be-suited professionals yesterday gave the outward impression that Kensal Green was firmly on a path to gentrification. Pleasant cafés and shops now break up rows of boarded-up buildings and rubbish-strewn plots. It is a familiar tale in London, where poverty is often just across the road from wealth. Violence, too, is never far away. And beneath the façade, shooting and murders have rocketed in an area some know as "murder mile''.

Five this year so far, against none in 2002. There have also been six attempted murders and seven serious shootings.

Drugs are at the root of most of it, of course. A hard core of about 200 Jamaican and black British gunmen, belonging to 20 gangs, run the capital's cocaine market. In the past year, more than 20 people have died in crack-related shootings in London. Since January, there have been more than 100 shootings. Police have seized more than 300 firearms. They know that is a tiny fraction of the total.

Operation Trident investigates about 70 murders a year. That is about one third of London's annual killings. But never before has a child been killed. A 14-year-old boy was injured last year in a shoot-out, but he was a bystander caught in cross-fire. So Toni-Ann's murder plumbs new lows, and detectives are hoping the criminal community itself will seek to identify the culprit. They believe its members will help the police to bring them to book.

Chief Superintendent Andrew Bamber, Brent's borough commander, said: "This catastrophic incident will have a devastating effect on my community.'' Neighbours certainly felt it. They recounted how Toni-Ann was brought out, gently cradled in the arms of an ambulanceman. She was dead on arrival at hospital.

Ch Supt Bamber pleaded for help. He said: "We don't want to investigate your murder, your child's murder or that of a member of your family.''

Norman Brennan, director of Crime Trust, said: "If we as a society truly care about the brutal assassination of a seven-year-old girl then those who know the identity of the killer must come forward.''

Det Ch Supt Coles said: "All we know is four shots were heard and that there was a female scream. We assume the female scream was young Toni-Ann. She was deliberately killed and we have to assume that it was because she was a witness to the crime.''

The killing of a child provokes public outcry. Remember 10-year-old Damilola Taylor, stabbed to death with broken glass in November 2000 as he walked home from school in Peckham, south-east London?

This, though, was even more calculated, saying something about life in Britain 2003. She had had a hard enough life, and she met a terrible death. But will the murder of Toni-Ann change anything?