The cause of death was determined two days after the 25-year-old Battle was found dead in her West Hollywood home, Los Angeles County Coroner’s Lt. Fred Corral said.
The group was featured on rapper Pitbull’s hit song “Wild Wild Love” earlier this year. Battle told The Associated Press in July that the collaboration gave the group a platform to launch its debut single, “Ugly Heart.”
A posting on G.R.L.’s Twitter account on Saturday said, “Words cannot express the depth of our loss. Simone’s incredible talent was only surpassed by the size of her heart.”
“We will carry her memory with us in everything we do,” the posting continued.