Fans of GB Leighton may have bummed to hear that the Minneapolis singer-songwriter canceled a gig scheduled for Thursday night at Shank Hall.

Now, they know the reason.

Brian Leighton, lead vocalist, guitar player and songwriter, announced on the group's Web site that he is entering rehab for an alcohol addiction.

Here is the text of Leighton's letter to fans.

To the friends and fans of gb leighton:

I've hit another crossroad in my life. Twenty years of the bar business has finally taken its toll on me, so...

I've checked myself into a 28-day program at Hazelden. I have tried outpatient programs, but have found that when I' min treatment during the day and in a bar that same night facing my demons, it doesn't work. So I have to remove myself from bars altogether; I have to find the old Brian again. If I'm honest with myself and with my fans, it's a huge first step. Ironically, when asked 15 years ago in a radio interview where I'd see myself in twenty years, I jokingly replied "Hazelden." Be careful what you wish for. Honestly, though, I need to be healthy again, physically and mentally.

I apologize to my fans and to all the bars that are going to have to take a rain check for the month of February. I didn't plan this in my life. But now is the time to deal with it. Please know that as scared as I am, I am also very excited about my future and the future of gb leighton.

I hope you see better shows from em with more energy and excitement. There's a huge light at the end of this tunnel. I'm chasin' it and I'm gonna stand in it soon.

I can't thank you enough for all the support you've shown me in my life.

I'm gonna miss ya!

See you in a month,

Brian

Singer Howie Day, slated to appear at Shank on Sunday, canceled the show and the remainder of his tour citing an illness.