Arizona Senator John McCain has passed away. He was 81.

McCain announced via a family statement on Aug. 24 that he would no longer seek treatment for his brain cancer. He had been diagnosed in 2017.

His daughter, Meghan McCain, released this statement on Twitter:

McCain, a five-year Vietnam POW, was elected to the Senate in 1986 and served alongside six U.S. presidents. He was the Republican presidential nominee in 2008.