McDonald's employees in nine cities have filed complaints against the fast-food giant, alleging they're victims of sexual misconduct, a labor group said Tuesday.

Employees of at least 10 McDonald's locations have filed complaints with the Equal Employment Opportunity Commission in the last several days, alleging sexual advances, lewd comments by supervisors and instances of inappropriate on-the-job behavior, the activist group Fight for $15 said in a statement Tuesday.

The group, which has long called on the company to set a $15 minimum wage, said in the statement that it plans to "challenge widespread sexual harassment faced by McDonald’s workers on the job across the country -- including groping, propositions for sex and lewd comments by supervisors -- that is all too often ignored by management."

The complaints, filed by workers in several cities -- including, Chicago, Detroit, Los Angeles and Miami -- allege instances where employees said they notified management after experiencing sexual harassment but were brushed off, mocked or, in some cases, met with retaliation, including termination, according to the Fight for $15.

McDonald’s Corp. said in a statement, “We are and have been committed to a culture that fosters the respectful treatment of everyone. There is no place for harassment and discrimination of any kind in our workplace. McDonald’s Corporation takes allegations of sexual harassment very seriously and are confident our independent franchisees who own and operate approximately 90 percent of our 14,000 U.S. restaurants will do the same.”

Among the complaints listed by the labor group were those of 15-year-old Breauna Morrow, a cashier in St. Louis, who said she reported a co-worker who had "repeatedly harassed her using graphic, sexual language," but her "supervisors did nothing."

"McDonald's advertises all over television saying it's 'America's best first job,' but my experience has been a nightmare," Morrow said in the group's statement. "I know I'm not the only one and that's why I'm speaking out, so others don't have to face the harassment I've gone through."

Tanya Harrell, a 22-year-old employee, told ABC News she'd reported that a co-worker at a New Orleans location had groped her, but instead of taking action, two store managers mocked her and told her "she was giving out sex appeal."

Harrell, who said that she'd been harassed in two separate incidents by two different coworkers, said she did not feel safe at her job but couldn't just quit because she cares for an ailing grandmother.

"I'm just doing a job that I was assigned to do. I did not go to work to be harassed," she said. "I didn't go to work to feel violated, exposed. ... That's the sad part about it."

The Fight for $15 also alleged that managers at a Durham, North Carolina, McDonald's told an employee that they wanted to have sex with her and even suggested a threesome with her and a coworker.

And, Kimberly Lawson, a 25-year-old crew member at a Kansas City, Missouri, site, said she'd actually shortened her work shift by an hour to avoid a manager who made lewd comments to her.

"He constantly made comments about my body," she said. "It was really uncomfortable."

Lawson told ABC News that she reported the incidents to a general manager but that nothing was done. Lawson said initially she was afraid of losing her job and her income but not anymore.

"We're not quitters and even though something as bad as this happened, it also can be, it can be changed," she said. "It's possible for it to be prevented if these corporations take the proper steps. ... I need to set an example for my child, you know, just as well as the other females out there."

Fight for $15, with financial support from the Time's Up Legal Defense Fund, set up a hotline and encouraged other workers to contact them and have their complaints reviewed by attorneys.

"As the country's second-largest employer, McDonald's has a responsibility to set workplace standards in both the fast-food industry and the economy overall," U.S. Rep. Jan Schakowsky, D-Ill., said in the statement. "The sexual harassment alleged by McDonald's cooks and cashiers in these charges is unacceptable."