Check out the Twitter exchange between Watson, Marin

Ottawa Mayor Jim Watson and Ontario's ombudsman, André Marin, have exchanged some heated words on Twitter and on CBC Radio's Ottawa Morning in recent days.

• On mobile? To view the Twitter exchange, click here.

It started Wednesday, when Marin held a news conference to support a bill that would give him powers to investigate municipalities.

He mentioned Ottawa's recent green bin contract audit, which cued Watson's entry into the fray.