This week, on the streets of Chicago, a shadowy group of "assassins" is on the loose.

But don’t panic. They’re stalking each other not with actual weapons but with water guns — and it’s all a big game.

StreetWars, as the wet multi-city spree is called, was created by New York securities attorney Franz Aliquo — and though it has police in Chicago worried, it began there on Monday as planned, so far with no arrests.

Around 100 participants, called agents or assassins, paid about $40 for the chance to be given profiles and photographs of other players they then have to hunt down in Chicago over a three-week period.

Click here to see the full report on MyFOXChicago.com.

They set to work tracking down their victims and ultimately going in for the “kill” — a nice, healthy squirt of H2O from a plastic pistol or a water balloon. Think paintball, with water instead of paint and in cities instead of woods.

The game continues until there’s only one agent left.

"We’ve all had the dream and desire to kind of be our own James Bond, and this was a good opportunity to try that out," Aliquo told MyFOXChicago.com.

There are rules: No shooting in bars, workplaces, buses, subways or el trains. Restaurants, stores and streets are all approved hunting grounds.

Aliquo, who calls himself the Supreme Commander of the Shadow Government, created StreetWars three years ago, in spite of what he characterized as New York City Mayor Michael Bloomberg’s efforts to shut it down.

"Mike Bloomberg, the mayor of New York, called me insane," he told MyFOXChicago.

The game has since been staged in Los Angeles, San Francisco, Vancouver, London, Vienna — and now, Chicago. Next up: London again, Toronto and Paris.

Chicago police warn that StreetWars is a risky business in this post-9/11 world, calling it “irresponsible” and saying it “infringes on the public’s safety.”

So far, however, no one has been seriously injured — one person sprained an ankle once, according to the Supreme Commander — and no one in any city has succeeded in stopping the StreetWars assassins in their tracks.

Click here to go to the StreetWars Web site.