A United Kingdom-based transgender Girl Guides Commissioner is under investigation after a photo surfaced on social media of the biological male dressed in risqué dominatrix clothing.

Leadership with Girlguiding, the British equivalent of the Girl Scouts, launched an investigation into the matter after the feminist website 4W revealed photos of Sully.

58-year-old Monica Sully, a bus driver, reportedly became a guiding Commissioner in July of 2021, overseeing girls of all ages in the organization, according to the Daily Mail.

Her appointment had upset some feminist campaigners, who argued that a biological male identifying as a woman should not hold a leadership position in the organization.

Campaigners unearthed photos on her Instagram page, including one with her dressed in leader dominatrix attire, holding a whip.

The caption read: "Now behave yourselves or Mistress will have to punish you #mistress."

Another photo showed Sully posing in black clothing, posing with an assault rifle, with another lying on the couch in the background.

According to the Daily Mail, another posted on her now deleted Twitter shows Sully posing with a large portion of her cleavage showing, with the caption: "Boobs, or did you want to see more?"

Angela Salt, the CEO of Girlguiding, said in a statement that "The safety and wellbeing of our members is our absolute priority."

"We follow rigorous recruitment and vetting procedures, have clear policies, and a volunteer code of conduct which volunteers are expected to follow to keep our members safe," she continued. "Girlguiding is aware of concerns raised. We are looking into this as a matter of urgency and will provide the necessary support and action in line with our compliance procedures."

Sully, who also goes by Monica Tetley on social media, has deleted both her Twitter account and her Instagram after the revelations.

In recent years, Girlguiding has taken a stance to be trans-inclusive, describing itself a "girl-only organization with a trans-inclusive Equality and diversity policy."

Their website says in a statement, "We treat trans girls and women according to the gender they have transitioned, or are proposing to transition, to. Meaning trans girls and trans women are welcome to be a part of our great charity."

"The benefits to Girlguiding of being fully-inclusive are significant. We recognize the huge impact Girlguiding can have on each young member and volunteer," it continued. "And it's vital that trans girls and women – like all other girls and women – can contribute their experiences, time, commitment and skills to our charity."

According to 4W, Sully's appointment received criticism, with some stating on social media that Sully took the position away from a biological woman.

One Twitter user said, "Why would someone do this? Why would you be SO insensitive towards women and girls that you would do this? I've managed my whole life without being involved with guiding and I'm a woman, it's hardly traumatic to not be involved."

"Another user suggested that the message it was sending to young women was possibly harmful, and that it simply demonstrated males would be readily able to gain leadership over females in exclusive spaces simply by identifying as women," 4W wrote.