Planned Parenthood Federation of America defended its practices on Thursday following allegations that the organization sells fetal tissue for medical research.

According to the Associated Press, Planned Parenthood wrote a lengthy letter to congressional leaders, including a report that says the videos that were used to accuse the company of malpractice were heavily altered by anti-abortion activists.

Planned Parenthood said the videos were distorted to misrepresent conversations between employees and anti-abortion activists, who went undercover as biomedical company employees to secretly video tape the encounter.

The recent report supports the organization's claims.

"It's increasingly clear that this attack on Planned Parenthood is a fraud based on a web of lies and deception," Executive Vice President Dawn Laguens said.

The Center for Medical Progress, an anti-abortion group, began releasing the videos in July, although Planned Parenthood continued to stand behind its claims that it does not illegally sell and harvest organs.

"The undercover videos show Planned Parenthood employees discussing reimbursement costs, which is legal," AP's Brian Melley writes in a Q&A.

"Planned Parenthood said in its letter to Congress that clinics receive $45 to $60 to recoup costs in California. Some clinics provide the tissue to university researchers for no fee," Melley continued.

One example that Planned Parenthood said proves that the videos were altered is the case of a Planned Parenthood official in Texas, who talked about lab protocols used to maintain tissue. The video was edited to make it sound like the official was talking about altering abortion methods to help harvest organs.

Fewer than one percent of 700 Planned Parenthood clinics provide fetal tissue for medical research. The fetal tissue is offered as a donation for research, and it is against the law to profit from them.

Washington State and California are the only places where fetal tissue from the organization is available. Affiliates and clinics in Oregon, Texas and Colorado have provided similar tissue but not fetal tissues.