The head of Planned Parenthood apologized Thursday for the "tone" of an official who discussed fetal organ donations in a new video that has sparked outrage against the abortion provider.

"Our top priority is the compassionate care that we provide," said President Cecile Richards, in comments released via a YouTube video. "In the video, one of our staff members speaks in a way that does not reflect that compassion. This is unacceptable, and I personally apologize for the staff member's tone and statements."

Richards was referring to comments by Planned Parenthood Director of Medical Services Deborah Nucatola, who was captured in an undercover video by anti-abortion activists talking about how some abortion clinics help women donate parts of aborted fetuses for medical research.

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The video has sparked a congressional investigation by Republicans, who say they want to find out if the group did anything illegal, either by profiting from the donations or performing partial-birth abortions.

Planned Parenthood hasn't addressed the partial birth abortion claims, but the group has said it doesn't profit from the donations and any compensation covers only the costs of collecting and transporting the human tissue to biomedical companies.

Richards reiterated that assertion on Thursday, saying the donation programs follow "all laws and ethical guidelines."

"I want to be really clear: The allegation that Planned Parenthood profits in any way from tissue donation is not true," she said. "Our donation programs — like any other high-quality healthcare providers — follow all laws and ethical guidelines."

The group that released the video, the Center for Medical Progress, says it plans to release up to a dozen more undercover videos featuring Planned Parenthood officials talking about collecting fetal tissue.