Republicans are "stoking the flames" of voter anger that have led to threats of violence against lawmakers, a top Democrat said Wednesday.

Rep. Chris Van Hollen (D-Md.), who serves as chairman of House Democrats' campaign committee as well as assistant to Speaker Nancy Pelosi (D-Calif.), accused the GOP of being inextricably tied to protesters who have threatened violence.

"This is now the face of the Republican Party. They have not taken responsibility," Van Hollen said of threats during an appearance on MSNBC. "They have, in fact, joined in this kind of activity. There is no denying the fact that they are stoking the flames here."

Democrats have reported an uptick in death threats and other threats of violence since a Sunday healthcare vote. Capitol Police briefed lawmakers on safety issues Wednesday, and House Majority Leader Steny Hoyer (D-Md.) pleaded for bipartisan cooperation on the issue while other Democratic lawmakers blamed the GOP.

"I think the danger is that the Republican Party has become so hijacked by the extreme right, they worry that if they criticize that behavior, they're going to lose that support," Van Hollen said, accusing the GOP of playing a "double game."

Lawmakers whipped protesters up into a frenzy during this weekend's protests on the Capitol against healthcare legislation. Those protests took on a taint, though, when racial and homophobic slurs were used against Democratic lawmakers.

House Republican Leader John Boehner (R-Ohio) called threats and verbal assaults against members "unacceptable" during an appearance Wednesday on Fox News.