Washington ? AOL’s chief technology officer is stepping down and the firm has fired two other people following last month’s massive data breach that caused more than 36 million member search queries to be released on the Internet, according to an internal memo and a source familiar with the matter.

In addition, the company has begun notifying dozens of individuals whose Social Security or credit card numbers were part of the exposed data, said the source, an employee who spoke on the condition of anonymity because it involved a personnel issue. The data came from 658,000 members who used AOL’s search engine between March and May.

The news comes as AOL’s profits have been falling and the company, in an effort to reverse its fortunes, is eliminating subscriptions and focusing more on advertising revenue. Maureen Govern, whose division was responsible for the breach, decided to leave immediately, according to an in-house announcement by AOL chief executive officer Jonathan Miller. The individuals fired were the researcher who posted the data and the researcher’s supervisor, the source said.

“After the great lengths we’ve taken to build our members’ trust and be an industry leader on privacy, it was disheartening to see so much good work destroyed by a single act,” Miller said in a separate company memo. “This incident took place because some employees did not exercise good judgment or review their proposal with our privacy team.”

Miller said AOL will set up a task force to reconsider how long it saves data, including search terms such as those disclosed last month on an AOL Web site intended for academics who study how people search the Internet. The firm also will further restrict internal access to search data and other “potentially sensitive” member data, even if it is made anonymous with a random identification numbers or not linked to an individual’s account, the memo said.