U.S. Sen. Al Franken is facing an investigation by the Senate Ethics Committee after a Los Angeles radio host revealed on Thursday that Franken kissed and groped her against her will in 2006.

The Minnesota Democrat did not deny the account by Leeann Tweeden that he kissed her without consent while they were rehearsing a comedy skit during a 2006 USO tour of the Middle East and Afghanistan, about two years before Franken was elected to the U.S. Senate. She also posted a photograph — which she learned about after the fact — of a grinning Franken, his hands reaching at her breasts as she slept.

"I'm still angry at what Al Franken did to me," Tweeden wrote on the website for KABC Radio in Los Angeles, where she hosts a morning show. "Every time I hear his voice or see his face, I am angry."

Franken first issued a brief apology before releasing a much longer statement of remorse, saying women like Tweeden "deserve to be heard, and believed when they share these stories." He echoed a call from senators of both parties that he be investigated by the Senate Ethics Committee, and said he would "gladly cooperate."

"I don't know what was in my head when I took that picture, and it doesn't matter," Franken said in the statement released by his office. "There's no excuse. I look at it now and I feel disgusted with myself. It isn't funny. It's completely inappropriate. It's obvious how Leeann would feel violated by that picture. And, what's more, I can see how millions of women would feel violated by it — women who have had similar experiences in their own lives, women who fear having those experiences, women who look up to me, women who have counted on me."

The unwelcome kiss was part of a skit Franken had scripted for the USO visit. Under what Tweeden described as pressure from Franken to rehearse the bit, she wrote that he "mashed his lips against mine and aggressively stuck his tongue in my mouth."

Franken skipped a handful of Senate floor votes on Thursday, and disappeared from public view as reporters staked out his Senate offices. He was subject to a barrage of criticism from Democratic colleagues in Congress and back in Minnesota, the latest high-profile man to face the kind of accusations of mistreating women that have recently engulfed other national and state politicians and a string of prominent entertainment industry figures. Also, President Donald Trump tweeted late Thursday criticism about Franken in the wake of the allegations.

Franken has traveled in both those worlds: he was famous for decades before launching a political career, as a performer and writer for the long-running NBC-TV show "Saturday Night Live." He and Tweeden, a former model with a lengthy background in broadcasting, were both regular participants in USO tours, entertaining U.S. troops stationed overseas.

Tweeden, at a news conference a few hours after her account was published, was asked if she accepted Franken's public apology.

"The apology, sure, I accept it, yes," Tweeden said. "People make mistakes, and of course he knew he made a mistake, so yes, I do accept that apology."

She later added, in response to another question, that "I'm not calling for him to step down. That's not my place to say that."

On "Good Morning America" Friday morning, Tweeden said that it was up to the people of Minnesota to decide Franken's fate.

Franken has been a vocal supporter of the #MeToo movement on social media, in which women shared stories of unwanted advances or worse by men. A few weeks ago, Franken gave a Minnesota charity thousands of dollars in campaign contributions he'd received from disgraced Hollywood producer Harvey Weinstein, the subject of accusations by multiple women.

On Thursday, other Democratic campaigns were scrambling to give away money they'd received from Franken's Midwest Values political action committee. Franken has been a prolific Democratic fundraiser in recent years.

"I am proud of Leeann Tweeden and the strong men and women who have bravely spoken out against sexual harassment and shed light on this important issue. This takes tremendous courage," wrote Angie Craig, a Minnesota congressional candidate, in announcing that she had donated $15,000 that Franken had steered toward her campaign in the state's Second Congressional District.

As of Nov. 6, Franken's Midwest Values PAC had distributed $115,000 to 16 Democratic Senate candidates and $25,500 to nine Democratic House candidates, including Reps. Keith Ellison and Betty McCollum of Minnesota, the Center for Responsive Politics reported.

The list of candidates announcing they would donate Franken's campaign cash to charity included Democratic Sens. Tammy Baldwin, Jon Tester and Claire McCaskill.

"This should not have happened to Leeann Tweeden," Minnesota Sen. Amy Klobuchar said in a statement. "I strongly condemn this behavior and the Senate Ethics Committee must open an investigation. This is another example of why we need to change work environments and reporting practices across the nation, including in Congress."

Senate Majority Leader Mitch McConnell and Senate Democratic Leader Chuck Schumer both called for an ethics investigation into the incident, though the behavior in question was before Franken was a senator. Asked about the incident at a news briefing, White House spokeswoman Sarah Huckabee Sanders also said a Senate investigation would be appropriate.

Calls for a Senate investigation were widespread — including from Minnesota Gov. Mark Dayton and others. There was less immediate clamor for Franken to resign, though Minnesota Republican Party Chairwoman Jennifer Carnahan called on him to step down. Two DFL candidates for governor, state Rep. Erin Murphy and State Auditor Rebecca Otto, also said Franken should resign from the Senate.

Franken followed his years on "Saturday Night Live" with a series of satirical books about politics and a nationally syndicated radio show. He parlayed that celebrity into a political career in Minnesota, the state where he grew up and graduated from high school. He was elected in 2008, after a bruising campaign against Republican Sen. Norm Coleman that ended with the two separated by only a few hundred votes. A protracted recount and legal battle ensued, and Franken finally joined the Senate in 2009.

Franken's decades in comedy yielded a trove of off-color and offensive jokes that dogged him through his first campaign, including a raunchy satire he penned for Playboy. Minnesotans reelected him by a wide margin in 2014. In recent months, he had emerged as a leading congressional critic of the Trump administration, and had even been mentioned as a possible presidential contender for Democrats in 2020, though he said publicly he did not plan to run.

The USO trip in question took place just before Christmas 2006. Tweeden was on her ninth USO tour at the time, introducing entertainers that included musical acts and the Dallas Cowboys cheerleaders. Franken, the headlining comedy act, pitched the idea of having her join him in performing a humorous skit — one that included a kiss she said he'd scripted.

On the day of the show, she said, the two were alone backstage and Franken suggested they rehearse the kiss. She said she tried to laugh it off, but he "continued to insist, and I was beginning to get uncomfortable." Eventually, she said, she agreed.

"[Franken] came at me, put his hand on the back of my head, mashed his lips against mine and aggressively stuck his tongue in my mouth," Tweeden wrote. "I immediately pushed him away with both of my hands against his chest and told him if he ever did that to me again I wouldn't be so nice about it the next time. I walked away. All I could think about was getting to a bathroom as fast as possible to rinse the taste of him out of my mouth. I felt disgusted and violated."

She wrote that Franken "repaid me with petty insults, including drawing devil horns on at least one of the headshots I was autographing for the troops." And it was on the flight back to the U.S., she later learned, that he was photographed reaching at her chest as she slept.

The apology that Franken issued Thursday was elaborate and wide-ranging.

"The first thing I want to do is apologize: to Leeann, to everyone else who was part of that tour, to everyone who has worked for me, to everyone I represent, and to everyone who counts on me to be an ally and supporter and champion of women," Franken wrote. He went on to say that "what people think of me in light of this is far less important than what people think of women who continue to come forward to tell their stories. They deserve to be heard, and believed. And they deserve to know that I am their ally and supporter. I have let them down and am committed to making it up to them."