Fall Out Boy have been lambasted by an angry mother for voicing their opinions on homophobia.

The band were performing at the Cricket Arena in Charlotte, North Carolina when outspoken bassist Pete Wentz spoke out against people with prejudices.

But a mother was seething, saying that a concert is not a place to voice what she saw as political views to a young audience.

The email, which now appears on the band�s website reads: �The ticket said 'all ages,' and your band was very foul-mouthed and anti-morals. Charlotte is not the demoralized city that liberal San Francisco and other cities across the North and West are.

�I had looked forward to this concert with my girls for months (and)I didn't spend over $200 on gas, food and, unfortunately, shirts for you to give your own personal political testimony. ... This was a concert, not some liberal homosexual rally."~

She continued: "I am not the only parent with morals that had children at this concert ... your responsibility was to sing your songs. When you opened your mouth to talk, you blew it.

"Here's to your band being just another Spice Girls, looking back and remembering the good times and 15 minutes of fame, because you (underestimated) who pays your bills. By the way, my children will not be a part of your sick idea of family."

In response, as mtv reports, Wentz said: The only thing I said in Charlotte was, 'You can leave this show and say, "I think this guy is an arrogant jerk," or think, "This band is better than this one," because these are your opinions.

�The only thing we consider unacceptable is for you to engage in sexist, racist or homophobic behaviour. If you do, we don't want you as a fan. Return our merch and leave.' "

He added: "I encourage fans of our band to grow up to become good people and to change the world. Unfortunately, I don't believe that treating other people as inhuman is acceptable.

�If that is offensive to you, I apologize, but we don't want you to be part of our fan base. (Our show) is not a liberal homosexual rally, but at the same time, it will never be a Ku Klux Klan rally. We don't need to sell tickets that badly."