Boston ? Prosecutors said they would not pursue charges against two men who planted electronic devices around the city as part of a botched advertising campaign after the pair apologized Friday for causing a bomb scare.

Peter Berdovsky, 27, and Sean Stevens, 28, also performed community service at a rehabilitation center in a deal with prosecutors.

In contrast to their first court appearance in January, when they mugged for the camera, the men offered contrite apologies and said they never expected the stunt to cause any turmoil.

The two were accused of planting about three dozen battery-powered devices Jan. 31 in Boston and Cambridge.

The devices, a promotion for Cartoon Network, had lights that created images of a cartoon character making an obscene gesture.

Fears of terrorism arose when the devices were discovered in a subway station and on a bridge, among other locations. Bomb squads were deployed, and highways, bridges and some transit stations were temporarily closed.