QUEBEC - Quebec's lobbying commissioner has launched a probe into the Quebec City arena project.

The commissioner announced today that, after examining documents submitted by the municipality, there was reason to believe a violation of the province's lobbying ethics and transparency law had been committed.

That law says lobbyists must be registered and it sets out a variety of penalties for non-compliance -- up to penal prosecution.

The commissioner's statement today was terse, and said nothing else about the alleged violation.

Quebec City is hoping to build an arena, essentially with public funds, to attract an NHL team back to the provincial capital.

The Quebecor media empire has signed a multimillion-dollar deal that would grant it the right to name and manage the building.

The arena project has already suffered its share of political controversy: the Harper government has washed its hands of the issue, refusing to fund the project; more recently, it has caused infighting within the Parti Quebecois.