Oregon's U.S. senators said Thursday that the Senate Ethics Committee should investigate Sen. Al Franken, Democrat of Minnesota, who a former coworker has accused of sexual harassment.

Sen. Ron Wyden, D-Ore.

"The allegations against Sen. Franken are serious. Harassment in any setting is clearly unacceptable. The Ethics Committee should investigate this matter," Sen. Ron Wyden tweeted.

Later, Sen. Jeff Merkley said the Ethics Committee should investigate Franken and that sexual harassment and assault are "never acceptable."

The Democrats' rebuke of a member of their own party and chamber comes after news reports that Franken groped and forcibly kissed Leeann Tweeden. The former model said the incidents occurred in 2006, when she was touring with Franken in Iraq and Afghanistan, performing skits to entertain U.S. troops.

Franken had written the scripts for the skits, and included a scene where he and Tweeden were to kiss. He insisted they practice the kissing scene, she said, and "he 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."

"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," wrote Tweeden, now a radio personality at a Los Angeles station. "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."

Franken later posed for a photo with his hands over Tweeden's breasts as she was sleeping on a military plane flying back from Afghanistan. The photo has since gone viral.

Franken publicly apologized to Tweeden, but said he did not remember the kissing scene practice the same way she did. His office released a statement saying the photo was intended to be funny, though he also offered his apologies.

Franken also called for a Senate investigation into his conduct and said he will "gladly cooperate" if one is launched.

The news comes as Franken is promoting a new book and seeing his star power rise as Democrats have begun to consider him as a possible challenger to President Trump in 2020.

-- Gordon R. Friedman

503-221-8209; @GordonRFriedman