Canadian musician Alice Glass has posted a statement accusing Ethan Kath, her former bandmate in the duo Crystal Castles, of sexual assault.

Writing on her website, she says that she and Kath, whose real name is Claudio Palmieri, first met when she was in high school. She details that subsequently, “over a period of many months, he gave me drugs and alcohol and had sex with me in an abandoned room at an apartment he managed,” she writes. “It wasn’t always consensual.”

She accuses him of further abuse after the pair had formed Crystal Castles and began touring the world. “He became physically abusive. He held me over a stair case and threatened to throw me down it. He picked me up over his shoulders and threw me on to concrete… He forced me to have sex with him or, he said, I wouldn’t be allowed to be in the band anymore.” She also accuses him of controlling her diet, clothing and finances and laughing when an unnamed recording engineer sexually harassed her.

Crystal Castles performing in Austin last month. Photograph: Jack Plunkett/Invision/AP

Kath has denied the accusations. “I am outraged and hurt by the recent statements made by Alice about me and our prior relationship,” he said. “Her story is pure fiction and I am consulting my lawyers as to my legal options. Fortunately, there are many witnesses who can and will confirm that I was never abusive to Alice.”

Crystal Castles formed in 2006, making raw electronic pop, and went on to release three albums. Glass left in 2014, explaining: “My art and my self-expression in any form has always been an attempt towards sincerity, honesty and empathy for others. For a multitude of reasons both professional and personal I no longer feel that this is possible within CC.” She was replaced by vocalist Edith Frances, with the new Crystal Castles lineup releasing the album Amnesty in 2016.

The remaining dates on the band’s current US tour have been cancelled in the wake of Glass’s accusations.

Glass says she’s speaking out now thanks to “the momentum that’s been created recently by the many courageous women who have opened up about their own stories,” referring to the recent wave of sexual harassment and assault accusations against entertainment industry figures.