(CNN) The White House on Thursday dismissed the latest video accusing Planned Parenthood of selling fetal organs and tissue, calling the group behind the sting "extremists on the right."

"There's ample reason to think that this is merely the tried and true tactic that we have seen from some extremists on the right to edit this video and selectively release an edited version of the video that grossly distorts the position of the person who is actually speaking on the video," White House Press Secretary Josh Earnest said. "And Planned Parenthood has indicated that's what has occurred here."

The Center for Medical Progress, an anti-abortion group, released its fourth video Thursday that claims Planned Parenthood is breaking the law by selling fetal tissue.

David Daleiden, head of the group, released a statement Friday defending its investigation against the White House's allegations.

"Planned Parenthood and its political allies are using every means possible to try and silence us and suppress investigative journalism but none of these bullying tactics change the facts our undercover investigation continues to prove -- that Planned Parenthood illegally harvests, traffics and sells aborted baby body parts for profit," he said. "The four video reports we have released so far are undeniable to anyone who watches them and they prove that Planned Parenthood is engaged in a gruesome and inhuman enterprise."

Following a similar format to the previous three clips, the heavily-edited video shows actors posing as researchers speaking with organization officials. The group has also posted longer clips claiming to be unedited to its website.

Planned Parenthood has repeatedly denied that it has done anything illegal.