WHAT would you do if someone pointed a gun at you on the street?
  
“I’d shoot them,” replies police Inspector Gareth Reiss, on the frontline with CO19, the firearms division of the Metropolitan Police.
  
His boss Bill Tillbrook says: “We are dealing with very dangerous people. We are talking about life or death situations – split second decisions.”
  
In The Line Of Fire (ITV1, Tuesday, 9pm) gets up close and personal in the fight against gun and gang crime which has plagued Britain’s major cities.
  
Last week it was revealed that Manchester is on the brink of shedding its “Gunchester” image after a crackdown on the city’s gangs.
  
Home Secretary Jacqui Smith hailed the city’s progress as an example to the rest of the nation. That includes London, where on average two people are shot every day.
  
The two-part documentary filmed with CO19 officers at a time when the Met Police were on trial for the shooting of Jean Charles De Menezes, gaining unique access and following officers for four months on live operations.
  
It features footage as they respond to life threatening incidents, tackling gang members who show no fear of turning their guns on the police. That includes confronting kids with guns, now becoming commonplace.
  
Armed police are filmed racing to help an unarmed officer stuck in a bullet-riddled car, who has been shot at five times. The subsequent three hour search for the gunman is fraught with risk, jeopardy and false alarms.
  
Another incident involves a man suspected of drawing a gun in a nightclub. Officers smash the window of his car and drag him from the vehicle. When he fails to comply, they fire a 50,000 volt Taser gun, knocking him to the ground.
  
For every six officers who apply to join CO19, only one will get in. Every six weeks each member is put through three days of intensive training to ensure they are still fit to carry a gun.
  
Inspector Matt Twist has spent three years with the department. He says: “In a fraction of one second you have to decide whether or not you are going to use what could be potentially lethal force.”
  
Some 14,000 gun and knife incidents were reported in London in 2007, with a worrying trend emerging. The age of both the victims and the perpetrators of gun crime is falling drastically. In 2007, 190 children under the age of 17 were shot by armed criminals.
  
“The thing I personally find shocking is the age of some of the victims, where you’re looking at children, really, who have been involved in gang violence and ended up getting shot,” adds Insp Twist.
  
“And often that, unless there’s something striking about the incident, it’s not newsworthy. And that, for me, is a little bit shocking because what does that say about how concerned we are about it?”
  
He adds: “Ten years ago probably the higher echelons of the criminal fraternity were using firearms for specific purposes to settle scores or commit armed robberies.
  
“Now there are children of 14, 15, 16 using guns to settle disputes that would have previously been fights in the playground or fights after school. It is actually quite scary, if at age 14 or 15 you are prepared to use guns to shoot other people, then God knows what is going to happen in the next five years.”
  
Pc Warwick Jones points out that the stakes are being raised for CO19 officers. “Our worry is the age now of the people that are carrying guns, because it is not going to be long before someone in the department, I would imagine, shoots a 14-year-old or 15-year-old boy and we are going to get absolutely slated.”
  
In The Line Of Fire shows police using levels of aggression which may surprise some viewers. Officers are trained to physically and verbally dominate suspects, firing their guns only as a last resort.
  
“To the outside looking in, it looks oppressive and aggressive but what is the alternative?” asks Pc Jones. “Do we get into a fight with these people and start grabbing our guns? They need to be controlled early.”
  
During 2007, CO19 were called out on 8000 separate occasions. But they fired their guns a total of just two times and three people were killed. As one officer puts it: “You read the papers and we’re getting branded as trigger happy, and you look at how many times a firearm is discharged.
  
“If you get it wrong, its pages and pages for weeks and weeks and months and months. Get it right and it’s no news.”

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