UNDATED (AP) – Looks like PSY was biting the hand that feeds him – even before it started feeding him.

The South Korean rapper who became an Internet sensation with his song “Gangnam Style” now says he’s sorry for taking part in anti-U.S. protests several years ago. Park Jae-sang came out with a statement of regret after it was revealed he was involved in concerts protesting the U.S. military presence in South Korea in the early stages of the Iraq war.

At a concert in 2004, the rapper performs a song with lyrics about killing “Yankees” including the lyrics: “Kill their daughters, mothers, daughters-in-law, and fathers/Kill them all slowly and painfully.”PSY now says he’s “deeply sorry” and that his language was “inappropriate.”

PSY attended college in the U.S. and has even performed in front American servicemen and women.