A bipartisan group that includes former lawmakers, military leaders and diplomats is urging Congress to create an independent commission to investigate the Jan. 6 attack on the Capitol.

Toward that end, the National Council on Election Integrity is launching a $250,000 digital ad campaign inside the Beltway on Tuesday to spur congressional action on a 9/11-style commission at a time when partisan bickering has stalled creation of such a panel. The group is a project of Issue One, a nonpartisan government watchdog group.

“Congress should act expeditiously to pass legislation to create a bipartisan and independent commission, modeled on the 9/11 Commission, to thoroughly investigate what happened, how it happened, and to identify what steps must be taken to prevent this from ever happening again,” the National Council on Election Integrity said in a statement.

“Congress should provide the commission with subpoena power, have an equal number of Republicans and Democrats, and build on the oversight committee work of Congress, various law enforcement reports, and intelligence reviews of the events leading up to January 6,” the group added.

The group calling for action includes: Former Rep. Lee Hamilton, D-Ind., who served as vice chair of the 9/11 commission; former Rep. Tim Roemer, D-Ind., also a member of the 9/11 panel and an integral author of the House legislation that established it; and former Rep. Zach Wamp, R-Tenn., who cultivated bipartisan support for building the Capitol Visitor Center after the terrorist attacks.

 “We all have a patriotic duty to get to the bottom of what happened on January 6 and prevent future attacks,” Wamp said in a statement. “The images from that day — of rioters desecrating our U.S. Capitol while our elected representatives were seconds away from peril — remains a shocking and infuriating reminder that this country needs to come together and heal. An independent commission is necessary to determine exactly what happened so this doesn’t happen again.”

Other Republicans endorsing a Jan. 6 commission include former Tennessee Gov. Bill Haslam, former Ohio Rep. Deborah Pryce and former New York Rep. Susan Molinari.

“Members from both parties want to get this done. What transpired on January 6 was an act of domestic terrorism,” Roemer said in a statement. “We have a responsibility to thoroughly investigate what led to this attack, push back against the disinformation that is eroding faith in our democratic process, and ensure that this never happens again in our country. An independent and bipartisan commission is a step we can take right now to strengthen our democracy and national security.”

Congressional leaders have been gridlocked on various components of what the commission would look like, including the balance of power between Democrats and Republicans and the scope of what it would examine.

The National Commission on Terrorist Attacks Upon the United States was an independent, bipartisan commission created by legislation in Congress and signed into law by President George W. Bush in late 2002. That commission charged five Democrats and five Republicans with preparing a full and complete account of the circumstances around the Sept. 11, 2001, terrorist attacks.

The new ad campaign, which shows an image from the deadly Jan. 6 riot, will appear in a variety of outlets: The Washington Post, The New York Times, CNN, Politico and Axios. It will run through next week.

“It is time for members of Congress to come together to protect our freedom and safety, and to ensure this kind of tragedy never happens again,” the National Council on Election Integrity said. “Failure is not an option.”