9-Year-Old Girl Dies Hours After Being Placed Under Anesthesia for Dental Procedure: Reports

• A 9-year-old girl in California died hours after undergoing dental surgery under general anesthesia, Dreamtime Dentistry in Vista said in a statement obtained by PEOPLE
• San Diego Police Department is investigating and a cause of death has not yet been revealed
• "We are deeply saddened by the tragic passing of our young patient," Dreamtime Dentistry said in the statement

A 9-year-old girl in California reportedly died hours after being placed under general anesthesia to undergo dental surgery.

On March 18, the girl, who hasn't been named, had surgery at Dreamtime Dentistry in Vista, the dentist confirmed to PEOPLE in an email sent via a public relations firm.

According to a statement obtained by PEOPLE signed by Dr. Ryan Watkins — a licensed dentist who is trained in anesthesiology, per the dentist's website — the girl's death "occurred several hours after her completed dental procedure." A cause of death has not yet been revealed.

After the surgery, the girl was moved to a recovery room before being discharged, local Fox-affiliated station KSWB reported, citing the San Diego Police Department. 

The station added that authorities stated the girl slept during the car ride home before she was later found "unresponsive" after going to bed. Her family then called 911, per KSWB, citing police.

She was taken to Rady Children’s Hospital Emergency Department in San Diego, where she was later pronounced dead, the outlet stated.

The medical examiner has "listed the cause and manner of death as pending," NBC 7 San Diego noted.

A San Diego Police Department spokesperson told PEOPLE in an email, "We are still working on gathering information related to the incident and cannot release any statements at this time."

Dreamtime Dentistry's Dr. Watkins said in a statement obtained by PEOPLE, "We are deeply saddened by the tragic passing of our young patient, which occurred several hours after her completed dental procedure."

"The patient was referred to our office for dental treatment under general anesthesia due to her young age and acute situational anxiety," the statement continued.

"Throughout the procedure, she was continuously monitored by our dentist anesthesiologist, who is a Diplomate of the National Dental Board of Anesthesiology as well as a Fellow in Anesthesiology from the American Dental Society of Anesthesiology and an active member of the American Society of Dentist Anesthesiologists who has over 20 years of experience successfully administering general anesthesia on children, with no complications observed," it added.

Watkins' statement also said, "Following the procedure, she was discharged in stable condition—awake, with stable vital signs and protective reflexes intact—into her mother's care, following our standard post-anesthesia protocols," adding that the cause of death is yet to be determined and that an investigation by the medical examiner is underway.  

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"We cannot discuss specific details due to privacy laws and the active investigation. We respectfully ask for patience as the medical examiner completes their work, as premature speculation may cause additional pain to the family," the statement read, insisting that "the safety and well-being of our patients have always been and remain our highest priority." 

"While we understand the concerns and questions surrounding this tragic event, we respectfully ask for patience as the investigation proceeds. For the sake of the family and the integrity of the process, we encourage restraint regarding speculation," the post stated.

"Our hearts break for the family during this unimaginable time of grief, and we extend our deepest condolences as we maintain our focus on supporting the family and cooperating fully with the medical investigation," the statement concluded, adding that updates will be shared "when appropriate."

The San Diego Medical Examiner's Office didn't immediately respond when contacted by PEOPLE for additional information.