BOSTON -- At least nine electronic devices, planted at bridges and other parts of Boston as part of a marketing campaign for a late-night cartoon, threw a scare into the city Wednesday.

Highways, bridges and a section of the Charles River were shut down and bomb squads were sent in before authorities declared the devices were harmless.

"It's a hoax -- and it's not funny," said Gov. Deval Patrick.

Turner Broadcasting, parent company of Cartoon Network, said the devices, which consisted of magnetic, blinking lights, were part of a promotion for the TV show "Aqua Teen Hunger Force."