The tragic death of TikToker Emilie Kiser’s 3-year-old son is under investigation.

One day after authorities in Arizona shared Trigg Kiser had died May 18 following a nearly week-long stay in the hospital, they have confirmed they are formally looking into the matter.

“Our thoughts and deepest condolences are with the child’s family and loved ones during this unimaginable time,” Chandler Police Department spokesperson Sonu Wasu said in a statement to E! News May 19. “The investigation into the circumstances surrounding this incident remain ongoing. This is still an open investigation.”

“Out of respect for the family’s privacy,” Wasu continued, “we will not be releasing additional details until the investigation is closed.”

E! News has reached out to the Kiser family for comment.

Officers responded to a drowning call May 12 at the content creator’s Arizona home, where they found the toddler unconscious after being pulled out of a pool in the backyard of the property, according to NBC affiliate KPNX. After first responders performed CPR on site, Trigg was taken to Chandler Regional Hospital and later Phoenix Children’s Hospital, where he died after six days in critical condition.