Nintendo unveiled LEGO City: Undercover during its E3 press conference and it looks to be an open-world type of game in the vein of the GTA series (but probably minus any LEGO strippers, violence and such). Players will interact with the game using the GamePad to scan scenes and make calls to dispatch.
A 3DS version will also be released with its own storyline adjustments for a more tailored title.
(Via Nintendo)