New Delhi, June 14 -- Bill Ritter, who has fronted the WABC-TV Eyewitness News broadcast in New York City for 27 years, told viewers at the end of Friday night's program that he is stepping away from the anchor desk after being diagnosed with Alzheimer's disease. He will not leave the station entirely, the 11 p.m. anchor said, but will instead take on a reporting role devoted to covering the disease he is now fighting.

Ritter's announcement was delivered in the format that has defined his on-air voice, a stretch of plainspoken script that walked viewers through the diagnosis, the timeline, and what he wants to do next. "I'm done anchoring at WABC," he said, "unless someone finds an amazing cure, and really soon." The line, distinctive fo...