SACRAMENTO, Calif. — Governor Schwarzenegger’s office on Wednesday rejected a request that it release several hours of audiotape that contained the governor’s now infamous comments about the mingling of “black blood” and “Latino blood.”

The letter from Mr. Schwarzenegger’s legal affairs secretary, Andrea Lynn Hoch, came in response to a demand from the Republican governor’s Democratic opponent in the November election, state Treasurer Phil Angelides.

Ms. Hoch said the audio files were obtained without authorization from a password-protected area of the governor’s Web site. She also said they “were accessed in a way that would suggest to any reasonable person that the files had not been posted for public distribution.”

Mr. Angelides has acknowledged that members of his campaign staff downloaded the audio files from the Web site and leaked a small portion of them to a Los Angeles Times reporter.

The recordings were from a speechwriting meeting in the governor’s office last March that included Mr. Schwarzenegger and a handful of aides. At one point, the governor and his chief of staff discussed the possible ethnicity of a Republican assemblywoman.

Referring to temperament, Mr. Schwarzenegger said that whether Cuban or Puerto Rican, “They are all very hot.” “They have the, you know, part of the black blood in them and part of the Latino blood in them that together makes it,” Mr. Schwarzenegger says on the recording.

He apologized for the remarks the next day, and the assemblywoman said she was not offended.

Mr. Angelides and his campaign officials maintain aides did nothing wrong in accessing the audio files.

“Governor Schwarzenegger is well aware that these audio files were as publicly available as a children’s book in a public library, yet now his office is making false accusations and using legal tricks to keep these files from becoming available to the public,” Mr. Angelides’s spokeswoman, Amanda Crumley, said.

The aides downloaded the recordings after going to a link of a Schwarzenegger speech about Hurricane Katrina on the governor’s official Web site. They then shortened the Web address and reached a trove of other audio files.

Last week, Mr. Angelides sent a letter to Mr. Schwarzenegger’s office asking that roughly four hours of private recordings be made public.

Ms. Hoch said Mr. Angelides’s own statements suggest that his campaign gained access to the audio files “in an irregular way.”

She said the files were contained on an “extranet server” maintained by the governor’s office and were for use by his staff. The office permits reporters to have access to specific files via a link, but she said the directory can only be viewed through use of a password.

Further, Ms. Hoch said the audio files were exempt from public disclosure because they were prepared solely for internal use and would disclose the deliberative process in the governor’s office.

“If the recordings were released to the public, it would chill the flow of information within the governor’s office, and it would impede the governor’s ability to work with his speechwriters and others in performing his official duties and in communicating with the people of California,” Ms. Hoch wrote in her letter to Mr. Angelides’s campaign lawyer, Lance Olson.