Washington Attorney General Rob McKenna is gearing up to go after Backpage.com for its role in the juvenile sex trafficking industry.

We're told that later this week, McKenna will announce that he and a group of other A.G.s are jumping into the fight against Backpage as part of his "Pillars of Hope" initiative he launched earlier this year as president of the National Association of Attorneys General.

Upon election, each NAAG presidents selects an issue to focus on (climate change, financial fraud, etc) during their term. McKenna, who became NAAG president in June, picked human trafficking.

McKenna is scheduled to speak with non-profit groups associated with fighting human trafficking this Thursday, and follow that up with a meeting with the NAAG leadership council.

A spokeswoman for McKenna, Janelle Guthrie, would not provide details on how McKenna plans to address problems with juvenile sex trafficking on Backpage.com, but confirmed he is "working with other attorneys general on a solution" and said her office could release more information later this week.

McKenna is scheduled to speak with non-profit groups associated with fighting human trafficking this Thursday, and will follow that up with a conference call with the NAAG leadership council.

Last year, 21 state A.G.s sent a letter to Village Voice Media/Backpage.com demanding the company "follow the lead of Craigslist" and shut down their adult services ads.

McKenna was not among the A.G.s who signed the letter.

Guthrie said there are a "variety of reasons" why McKenna didn't sign the letter last year, and cited concerns about the timing of the letter, as well as feedback from law enforcement.

It's unclear whether McKenna has been in contact with Seattle Mayor Mike McGinn, who's been hammering Backpage all summer.