TORONTO -- Two major players on opposite ends of the state surveillance spectrum are set to debate the heavily contested topic in Toronto this spring.

Retired Gen. Michael Hayden, a former director of the National Security Agency in the U.S. will go head to head with Glenn Greenwald, the American journalist who reported on NSA leaks.

Greenwald received documents from former NSA analyst Edward Snowden and reported about them last year for the newspaper The Guardian.

The topic of the debate -- set for May 2 -- is "Be it resolved: State surveillance is a legitimate defence of our freedoms."

The event organizer -- Munk Debates -- says two other debaters are yet to be announced, one to join Hayden on the pro side and another to join Greenwald on the con side.

Tickets go on sale to premium members of the Munk Debates at 10 a.m. on March 4 and the organizer says if there are any left, they will go on sale to the general public at noon on March 6.