Two toddler brothers aged 3 and 1 were confirmed dead on Saturday August 15, after getting into a hot car on their own in Alabama.

The incident occurred outside the kids’ residence in Montevallo, Alabama and the Coroner Lina Evans said that Shelby County authorities responded to a call from the boys’ parents around 3:30 p.m local time.

The parents told authorities they thought the two boys had been playing in their rooms but discovered them unresponsive inside the vehicle. Shelby County Sheriff’s Office is investigating, but Evans stated that it was “just a tragic accident” as temperatures were in the high 80s in Shelby County on Saturday.

While an autopsy result is expected on Monday August 17, the tragic incident now marks the 16th and 17th children to die in a hot car in the U.S. this year according to KidsandCars.org.