Bartz saying she had been fired by Yahoo's chairman, according to the Wall Street Journal's All Things D blog, which was the first to report her departure.
"I am very sad to tell you that I've just been fired over the phone by Yahoo's Chairman of the Board. It has been my pleasure to work with all of you and I wish you only the best going forward," Bartz wrote.
The struggling search company has created an "executive leadership council" to help Morse run the company and to conduct a "comprehensive strategic review" aimed at getting Yahoo back on a growth track. The council includes Yahoo co-founders Jerry Yang and David Filo.
Bartz's tenure as CEO began in January 2009 after Yang announced plans to step down. She took over following an extensive courtship in which Microsoft tried to acquire Yahoo, but which eventually turned into a partnership between the companies.
That partnership hasn't paid off as well as Yahoo hoped. , and its display advertising business, where it historically was a leader, has begun to suffer too.