It only takes three words to cause a widespread controversy.

Canadian quartet The Tenors issued an apology via Twitter after group member Remigio Pereira held up a sign and added “All Lives Matter” to the Canadian national anthem “O Canada” at an MLB All-Star pre-game performance.

“The Tenors are deeply sorry for the disrespectful and misguided lack of judgment by one member of the group acting as a ‘lone wolf’ today during the singing of the Canadian national anthem at the Major League Baseball All-Star Game in San Diego,” the group wrote in the apology.

The musicians came under heavy scrutiny following Pereira’s actions on Tuesday, inciting a frenzy on social media.

“All Lives Matter” is a controversial phrase used to reject the “Black Lives Matter” movement. The group’s apology deems Pereira’s actions as “extremely selfish,” and also claims he acted as a “lone wolf.”

In addition, the statement indicates that the incident does not reflect The Tenors as a whole. Pereira has been removed from the group “until further notice.”