Yes, they did say that…
Hard to believe that even a British commentator could get away with mentioning “white power” in a sportscast, but this was 1968 and things have changed since then. What really struck me about this news-reel was that it was in black and white. The Mexico City Summer Games — in addition to the “victory ceremony, unfortunately overshadowed by politics” and what was going on outside the stadium — marked the beginning of live transmissions of moving images, and in color, making news-reels obsolete.
I took this video from The Guardian, but British Pathé has an online archive of their newsreels from 1896 to 1976 (color finally coming in the 70s, too late to save the news-reel as a media).