(CNN) - Someone shouted "baby killer" Sunday as an anti-abortion Democratic congressman was speaking on the House floor shortly after the chamber passed a sweeping health care reform bill with his help.
It wasn't clear from whom the shout came.
Rep. Bart Stupak, who opposed the bill over its abortion language until he reached a deal with the White House on Sunday, was speaking against a Republican motion to effectively kill the passed legislation Sunday night when several congressmen shouted him down.
As the speaker asked for the interruptions to stop, someone yelled "baby killer."
Congressmen groaned, and someone shouted, "Who said that?"
Just days earlier, Stupak, D-Michigan, was a hero of anti-abortion House Republicans who opposed the health-care bill. Stupak led a group of other anti-abortion Democrats who rejected the bill because they said it would allow federal funding for abortions beyond the current limits of cases of rape, incest or if the mother's life is in danger.
The objection threatened to scuttle the bill's chances in the House. But on Sunday, Obama struck a deal with the anti-abortion Democrats, saying he would issue an executive order to ensure that existing limits on federal funding of abortion remain in place.
That won the support of the anti-abortion Democrats, and the bill passed Sunday night on a 219-213 vote.
After the bill passed, Republicans introduced a motion that sought to send the bill back to committee and amend its abortion language, language that Stupak originally wanted. Stupak spoke against the motion, leading to the shouts from some Republicans.
The motion did not pass.
The "baby killer" outburst came about six months after Rep. Joe Wilson, R-South Carolina, yelled "you lie" to Obama during the president's speech to Congress. The House passed a resolution that month admonishing Wilson.
- CNN's Brianna Keilar contributed to this report.