The teen accused of killing her older sister had reportedly described 'suicidal and homicidal' thoughts to a witness

• Claire Miller, 14, was charged with homicide in the case of the death of her 19-year-old sister.
• A witness reportedly told police that Miller said she had "suicidal and homicidal thoughts."
• TikTok removed an account believed to belong to Miller after its videos went viral.

A Pennsylvania teen charged with killing her older sister is said to have had "suicidal and homicidal thoughts" before the death, a witness reportedly told police.

Claire Miller, 14, told the unnamed witness about these thoughts in a phone call, according to a court document obtained by Insider. The Manheim Township Police Department included the witness' claim in an affidavit of probable cause as part of its application for a search warrant on Miller's home. The document does not specify when the alleged phone call between Miller and the witness took place.

The new information about Miller's mental state was first reported by Lancaster Online and PennLive.

Miller was arrested on February 22 after investigators say she admitted to killing her 19-year-old sister, Helen, who had cerebral palsy and used a wheelchair. Miller "repeatedly" told police who reported to the scene, "I stabbed my sister," according to an arrest affidavit reviewed by Insider.

Police found a "large knife in Helen's neck, just above her chest," the affidavit said, and PennLive reported that the Lancaster County Office of the Coroner said Helen Miller died of multiple stab wounds.

A Manheim Township judge did not set bail in the case since Miller is facing a criminal homicide charge, police said in a statement. Though she's only 14, Miller is being tried as an adult in accordance with Pennsylvania homicide laws.

The crime caused a frenzy on TikTok, where users believed Miller ran the account @spiritsandsuchconsulting. The page had 32,000 followers and her last videos had millions of views on the app. Comments reviewed by Insider showed that some users discovered what appeared to be Miller's videos through the platform's For You Page.

After the videos went viral last week, TikTok removed the account for violating the platform's Community Guidelines, which do not allow users who "promote or are engaged in violence." TikTok did not confirm that the account belonged to Miller, but Insider verified that one video on the account appeared to show Miller's older sister, Helen.

Miller remains in prison awaiting her next court appearance on March 30, according to court records. An attorney for Miller did not respond to a request for comment.

This article has been updated.