Sia Calls Shia LaBeouf a 'Pathological Liar,' Claims He 'Conned' Her Into 'Adulterous Relationship'

Sia is speaking out about Shia LaBeouf after his ex-girlfriend FKA twigs sued him for alleged physical, sexual and emotional abuse.

“I too have been hurt emotionally by Shia, a pathological liar, who conned me into an adulterous relationship claiming to be single,” Sia, 44, wrote on Twitter over the weekend.

Sia did not provide further details of her allegation and reps for both the singer and LaBeouf did not immediately respond to PEOPLE's requests for comment.

LaBeouf, 34, starred in the 2015 music video for her song “Elastic Heart” alongside dancer Maddie Ziegler.

“I believe he's very sick and have compassion for him AND his victims. Just know, if you love yourself- stay safe, stay away,” Sia added.

Sia went on to send a message of support to the "cellophane" singer, 32. “Also I love you @FKAtwigs,” she wrote. “This is very courageous and I’m very proud of you.”

RELATED: FKA Twigs Sues Ex-Boyfriend Shia LaBeouf for 'Relentless' Sexual, Physical and Emotional Abuse

Related: Shia LaBeouf has this apology following his 2017 arrest

In the lawsuit, Twigs, born Tahliah Debrett Barnett, alleged that the actor sexually and physically assaulted her, according to documents obtained by PEOPLE.

"What I went through with Shia was the worst thing I've ever been through in the whole of my life," she said in an interview with The New York Times, going on to say that she didn't go to police at first to not harm his career and because she "thought her account would not be taken seriously."

The actor addressed the allegations in several emails to The Times by saying he was in no position "to tell anyone how my behavior made them feel."

"I have no excuses for my alcoholism or aggression, only rationalizations. I have been abusive to myself and everyone around me for years," he wrote to the newspaper. "I have a history of hurting the people closest to me. I'm ashamed of that history and am sorry to those I hurt. There is nothing else I can really say."

In a different email, however, he said that "many" of the allegations were not true but explained he owed the women "the opportunity to air their statements publicly and accept accountability for those things I have done."

"We tried to resolve this matter privately on the condition that Mr. LaBeouf agree to receive meaningful and consistent psychological treatment," her attorney Bryan Freedman previously told PEOPLE. "Since he was unwilling to agree to get appropriate help, Ms. Barnett filed this suit to prevent others from unknowingly suffering similar abuse by him."

In an Instagram post on Friday, Barnett opened up about her decision to speak out publicly.

"It may be surprising to you to learn that I was in an emotionally and physically abusive relationship. it was hard for me to process too, during and after i never thought something like this would happen to me," she wrote. "Which is why i have decided it's important for me to talk about it and try to help people understand that when you are under the coercive control of an abuser or in an interpersonal violent relationship leaving doesn't feel like a safe or achievable option."

The singer added that she hopes that sharing her experience "can truly" help others not feel alone and "shed a light" on how others can help loved ones in abusive relationships.

"My second worst nightmare is being forced to share with the world that I am a survivor of domestic violence," she added. "My first worst nightmare is not telling anyone and knowing that i could have helped even just one person by sharing my story."

If you are experiencing domestic violence, call the National Domestic Violence Hotline at 1-800-799-7233, or go to thehotline.org. All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.