It's a sign of the health of this city that it can absorb any dousing it gets.. He says no, he's just reached the age where he appreciates all the things he enjoyed about being young and now, in charge of his own life, he can indulge them again. As for me, I felt desperate to join in boys' rampaging terror, and was never allowed.And are these carnival assassins really going to confuse the police's instinct for terrorist detection? Hardly. Ernie sees him first and squarely discharges a blast of water on to the top of his head, putting Baz out of the game for 24 hours. All three of us emerge from the shoot-out high on the verve of a virtual murder.You wonder what drives men and women with jobs, mortgages, the trappings of grown-up life, to chase each other across the streets of London with water pistols, an army of over-grown kids living out film fantasies of being gun-slinging secret agents.As we are cruising past our target's house one night I ask Baz if neither of us has grown out of our childhood.

I cannot leave my house without sending a friend or neighbour out to check for snipers behind garden fences, or strange characters idling nearby. I carry a top-range water pistol for defence at all times.My target, a finance worker called Ernie who lives in Earls Court, is so edgy he travels everywhere by skateboard to make him more difficult to catch.My team-mate Baz and I have been hanging around his house for hours, befriending neighbours who are, unsurprisingly, curious as to why decent-looking citizens are crouching in bushes, whispering into mobile phones, and hiding in the back seats of cars under heaps of clothes.Our best attempt at a hit comes when Baz hides in the basement well of Ernie's block at 2am, gun cocked, waiting for me in a car outside to report the skateboarder's arrival. The combatants are jokers and kidults, rather than closet psychos, though the latter tendency has been reported emerging amongst the hard-core players.There is as much thrill in the paranoia as the kill No more quick trips to the local shops for me. It is a game of fantasy, closer to the ironic bravado of the Grand Theft Auto computer game series. By comparison Streetwars is sinister, but it is not however born out of the modern terror scene.

The police over in London have been similarly jumpy that citizens hanging around on street corners, acting suspiciously and taking aim at their fellow citizens with weapons, albeit brightly coloured plastic ones, could be mistaken for Jean Charles de Menezes.Streetwars is part of a new culture of urban games springing up across major cities. Streetwars prompted New York's Mayor Bloomberg to ask whether it was appropriate to play a game of gun-wielding terror in the post 9/11 world. In this extended circle of mutual destruction the last man standing takes the glory. The architect of this game, which has already been played in San Francisco, Vancouver and New York, is Franz Aliquo, a disaffected US lawyer with a penchant for Seventies suits who styles himself the Shadow Commander. The aim of the three-week tournament is to hunt down and "shoot" one of the other combatants, while in turn being stalked by another assassination team The bullets in this case are jets of water. But before that we all agree that hunky Martin Henderson was, well, hot You see? That's where the trouble starts Always.. Assassins come in many guises.