CNN's John King caught joking about 'Irish lives matter' on open mic during speech on immigrants
CNN's John King -- CNN Twitter screen grab

During a speech by Philadelphia's mayor at the Democratic National convention on the immigrant experience, CNN's John King was caught on an open mic making a joke about the speech.

Mayor Jim Kenney was addressing the convention goers and discrimination faced by early Irish immigrants, when King made his comment.

“Today, today, however, I want to share a Philadelphia story you probably don’t know," Kenney said. "In 1844, an early version of the Know Nothing political party held a rally here to protest the threat that Irish Catholic immigrants posed to the American way of life. They claimed these immigrants, these people like my family, were more like likely to commit crimes than native born citizen."

As Kenney was speaking, King quipped,“That’s the Irish Lives Matter movement,”  unaware the mic picked him up.

Kenney continued, "This rhetoric led to riots,” St. Michael and St .Augustine churches were burned to the ground. Some 20 people died. I’m telling you this story for one reason: It’s happening again. The Know Nothings have returned.”

Watch the video below via Mediaite: