BOSTON - Several illuminated electronic devices planted at bridges and other spots in Boston threw a scare into the city yesterday in what turned out to be a publicity campaign for a late-night cable cartoon. Most if not all of the devices depict a character giving the finger.

Peter Berdovsky, 29, of Arlington, was arrested on one felony charge of placing a hoax device and one charge of disorderly conduct, State Attorney General Martha Coakley said. He had been hired to place the devices, she said.

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.

Turner Broadcasting, a division of Time Warner Inc. and parent of Cartoon Network, later said the devices were part of a promotion for the TV show Aqua Teen Hunger Force, a surreal series about a talking milkshake, a box of fries, and a meatball.

Authorities are investigating whether Turner and any other companies should be criminally charged, Coakley said. It was not immediately clear who might have hired Berdovsky.

At least 14 of the devices were found, Coakley said.

In Philadelphia, Mayor Street's spokesman, Joe Grace, said one device was found attached to a commercial sign at Sixth and South Streets and there were possibly 55 others. A cease-and-desist letter was sent to Turner Broadcasting, threatening fines for violating zoning codes.

Grace said Philadelphia intended to recoup all costs associated with what he called "a stupid, reckless, irresponsible prank."

Staff writer Michael Matza contributed to this report.