The decorated director of The Cadets drum and bugle corps resigned Thursday after nine women accused him of sexual harassment and assault. The allegations against George Hopkins spanned four decades.

Youth Education in the Arts, the Allentown nonprofit that runs the Cadets, announced the decision on its website and called it a "painful moment for all those who care about The Cadets."

"Though he denies the allegations, he believes stepping aside is in the best interest of the organization. We agree. His resignation is effective immediately," the board of directors for Youth Education in the Arts, the Allentown nonprofit that runs the Cadets, said in a statement posted on the website.

 >> SPECIAL REPORT: He created a drum corps dynasty — and a legacy of alleged sex abuse over 4 decades in Pa. and N.J.

>> Sexual abuse in drum and bugle corps: Do you have a story?

Sean King, a longtime employee of the nonprofit, will be acting CEO, the board said.

Hopkins, 61, was hired by the Cadets in 1979 and became director in 1982. He has coached the troupe to an impressive 10 world championships while earning a spot in drum corps history as an innovator and mentor to hundreds of teens and young adults.

The activity can be likened to marching band, plus more theatrics and a grueling performance schedule that takes the members, who range in age from 16 to 22, coast to coast each summer.

>> Who are the Cadets? What to know about the drum corps dealing with sexual misconduct allegations

The Inquirer and Daily News reported Thursday that nine women accused Hopkins of sexual assault and harassment. Their stories span from 1980 to as recently as a few years ago and include accusations of lewd comments, groping, and rape. The women ranged in age from 16 to 37 at the time of the alleged incidents.

Three of the women were members of The Cadets when they say Hopkins abused them. Five worked for the organization at the time of the alleged incidents.

Megh Toth, one of the women, said she was sexually assaulted by Hopkins in 2006 when he crawled into her bed during an overnight business trip. She said Hopkins had insisted the two share a hotel room to save money.

"I said no the entire time. I didn't want this to happen," Toth said. "And then your brain just goes. Your fight is gone."

Thursday's revelations rocked the drum corps world, one of relatively small size but with devoted fans. Across online forums and social media platforms, many called not just for Hopkins to resign but for Drum Corps International, the sanctioning body for the activity, make sweeping changes to ensure members are protected from sexual abuse.

Some also called for the board of directors of Youth Education in the Arts to also resign.

The board became aware of several of the women's stories in January. They were provided, without the women's names, by Kevin Hahn, an attorney working on the women's behalf. Hahn told the board's attorney, Kimberly Spotts-Kimmel, that the women were willing to be interviewed if the nonprofit hired an independent investigator and Hopkins was suspended pending the outcome of the investigation, according to correspondence between the two.

The board hired Spotts-Kimmel's firm to investigate and did not suspend Hopkins. Hahn did not provide the women's names to the firm, as it represents the board.

In its statement, the board defended its handling of the situation.

"The investigation was conducted professionally and vigorously," the board said. "Unfortunately, there was no cooperation at all from anyone making those accusations. Despite our pleas for cooperation, we were told so long as George remained in his role, no one would allow herself to be interviewed or reveal any facts that might confirm the allegations. No responsible board of directors can take action based solely on anonymous allegations."

Earlier Thursday, Drum Corps International issued a statement calling the allegations "deeply concerning." It said it would assess what the Cadets were doing to investigate the allegations and whether any of its policies had been violated. The organization said it could sever its relationship with The Cadets if its policies had been ignored.