Mitt Romney responded Thursday to a news article describing him as a prep-school prankster who bullied a classmate by apologizing for past incidents that may have been harmful, adding that he has grown into a different person since his school days.

In 1965, a teenage Romney led a group that forcibly cut the hair of a student who wore his dyed-blond tresses long and was presumed to be gay, according to five of Romney’s classmates at the elite Cranbrook School in Bloomfield Hills, Mich., who were interviewed by The Washington Post.

Romney, the presumed GOP presidential nominee, denied any anti-gay animus.

“I had no idea what that individual’s sexual orientation might be. Going back to the 1960s, that wasn’t something that we all discussed or considered, so that’s simply just not accurate,” he told Neil Cavuto of Fox News Channel. “I don’t recall the incident myself, but I’ve seen the reports and I’m not going to argue with that. There’s no question but that I did some stupid things when I was in high school and obviously if I hurt anyone by virtue of that, I would be very sorry for it and apologize for it.”

The Romney campaign has often used the image of him as a prank-loving father and husband to show a more personal side.

Democrats and gay-rights groups seized on the incident from nearly five decades ago, suggesting that Romney’s past actions and present response raise character questions.

“Mitt Romney’s unwillingness to understand or acknowledge the gravity of his actions and sincerely apologize is a troubling suggestion of a lack of character,” said Joe Solmonese, president of the Human Rights Campaign.

The article appeared as the Romney team has been dealing with scrutiny over the departure of a gay national security spokesman, after social conservatives made an issue of his sexuality. Meanwhile, President Obama expressed his support Wednesday for same-sex marriage.

In a statement provided by the Romney campaign, a former fellow student recalled Romney as ”a thoughtful guy with a great sense of humor who cared about his classmates.”

“He would never go out and do anything mean spirited,” said the statement by Richard Moon. “Clownish, yes. Never mean.”