The Washington Football Team have been fined $10m (£7.3m) after a review by the NFL into workplace culture at the franchise.
The investigation found bullying and intimidation “frequently took place” and many described a culture of fear.
The review was led by independent counsel Beth Wilkinson, who interviewed more than 150 people.
“Numerous female employees reported having experienced sexual harassment,” the NFL said in a statement.
“In some instances, senior executives engaged in inappropriate conduct themselves, including use of demeaning language and public embarrassment.”
NFL commissioner Roger Goodell said the investigation had found a workplace culture that was “highly unprofessional” both “generally and particularly for women”.
Following the publication of the report on Thursday team owner Dan Snyder said “a lot of changes” had been made over the past 18 months, including the implementation of a “new and diverse leadership team” and a “comprehensive program of training”.
“It is now clear that the culture was not what it should be, but I did not realise the extent of the problems, or my role in allowing that culture to develop and continue,” Snyder said.
In addition to the fine the franchise are also obligated to report to the league twice a year for the next two years with updates about how they are following through on improving workplace culture.
Allegations of widespread sexual harassment and abuse came to light last year in a Washington Post report.