FLAGSTAFF, Ariz. (AP) — The top two officials at Grand Canyon National Park are among those facing disciplinary action following a federal report that found they violated policies on reporting and investigating allegations of sexual harassment in the park's river district.

The National Park Service's Intermountain Region director, Sue Masica, declined Thursday to say what specifics actions would be taken against Superintendent Dave Uberuaga, and his deputy Diane Chalfant. The possibilities, in general, range from a warning letter, a reprimand, and suspension to termination, she said.

"You kind of have to match the severity of the action by the individual with the previous records to what's appropriate for the particular circumstance," she said. "I'll be looking at all of that."

A complaint filed in 2014 by 13 former and current Grand Canyon employees prompted an investigation by the U.S. Department of the Interior's Office of Inspector General. The complaint alleged a 15-year pattern of abuse in the river district on rafting trips led by the Park Service.

Members of Arizona's congressional delegation said they were outraged and called for swift action.

The report focused on allegations lodged against four male NPS employees who pressured female co-workers for sex, touched them inappropriately, made lewd comments and retaliated when they were rejected. It also found that disciplinary actions were inconsistent when it came to sexual harassment and that the Grand Canyon's chain of command failed to properly investigate or report allegations of misconduct — a violation of Interior Department policy.

Masica said Uberuaga and Chalfant are responsible for complying with that policy. She set a May 1 deadline for disciplinary action against them, but the results likely won't be revealed publicly because they are considered personnel matters, she said.

A boatman who propositioned women for sex remains employed at Grand Canyon but is restricted from participating on river trips. Masica said he would be disciplined as well. Two other boatmen resigned in 2006 and 2013 after serving suspensions for sexual harassment. A supervisor who grabbed the crotch of a contract employee retired in 2015, according to the report.

Michelle Kearney, a former Grand Canyon river district ranger who signed on to the 2014 complaint, said she's pleased that the Park Service is "holding people accountable for this behavior."

Other reforms outlined by Masica include third-party reviews of a string of past disciplinary actions to ensure consistency and of a 2013 report by the Equal Employment Opportunity office that looked into similar sexual harassment complaints.

Masica vowed to develop comprehensive training programs, to apologize personally to those who filed the 2014 complaint and to separate the patrol functions of the river district from the support services for rafting trips. Grand Canyon National Park manages 280 miles of the Colorado River, providing emergency and medical services as well as guiding researchers, politicians and students on a dozen river trips per year.

Masica set deadlines within 2016 for the reforms, many of which she'll lead in implementing. She said the reforms hopefully would set a new tone and direction for the Grand Canyon, one of the nation's busiest national parks with more than 5 million visitors a year. Meanwhile, she said she'll push a message of zero tolerance for sexual harassment and hostile work environments.

"While dismayed at the work environment described in the report, I am committed to working to change the situation and keep similar situations from happening again," she wrote in response to the report. "The employees of Grand Canyon National Pak deserve nothing less than that."

Kearney praised the reforms as robust and healthy. She suggested that the Park Service seek help from the U.S. Justice Department's Office of Violence Against Women for resources in developing training programs.

The Park Service also should have at least two systems to report misconduct, sexual harassment and violence that are centered on the victim and confidential, she said.

"The system failed. We tried every avenue, and it failed," she said. "It needs to be reviewed. Those people in those positions need to have special training."