Modest Mouse have announced that guitarist Simon O'Connor will not be part of their upcoming dates following allegations that he sent inappropriate messages to a minor.

The US band posted the update on Instagram on July 31, stating: "Simon O'Connor will not be accompanying us on the upcoming tour." They also revealed that Les Savy Fav's Seth Jabour will take over guitar duties, adding only "Upcoming tour update" as the caption. No reason was given for O'Connor's removal, leaving the timing to speak for itself.

The announcement landed shortly after a Reddit user - claiming to be a 17‑year‑old fan - claimed O'Connor contacted her on Instagram after she liked several of his Stories.

In her July 26 post, she alleged he sent an "erotic image" and additional messages, including remarks about her "bikini pics," despite her age being visible on her profile. She said O'Connor deleted the messages within minutes, but she had already taken screenshots and shared them publicly.

O'Connor responded the next day on the band's subreddit, issuing an apology and attempting to explain how the exchange occurred.

He wrote: "Firstly, I would like to just state that I unequivocally oppose any sexual behavior towards minors, as a human and a parent it disgusts me."

He claimed he mistook the account for someone who had repeatedly created fake profiles to "mess with" him over the years.

He said: "This person creates multiple social media accounts and deletes them… but always posts similar photos that I often recognize from previous accounts."

According to O'Connor, he picked up his phone after a long night and saw what he believed was another prank account interacting with his posts. He said he replied with "a tasteless meme," a sticker reading "Simon calls your bluff," and a message intended as a "gotcha."

He wrote: "After a few minutes, I realized that I had made a mistake and this was not the person who I had dealt with before." He said he unsent the messages immediately and stopped responding.

O'Connor ended his post with a direct apology: "They didn't deserve to be put in that position… I can't change what's happened. All I can do is tell the truth, take responsibility for my mistake, and apologize."

Modest Mouse have not commented further on the allegations or whether O'Connor's removal is permanent.

The tour is due to kick off on August 4 in Ojai, California.