Two giraffes died at a drive-through safari and amusement park in Florida after lightning struck them in a “billion-to-one” accident, the park announced Tuesday. “We continue to mourn our two incredibly lovely and charismatic giraffe; they will both be sorely missed,” the park, Lion Country Safari, said in a statement. A 10-year-old female, Lily, and 1-year-old male, Jioni, died instantaneously after being struck in the lightning storm six weeks ago. The two giraffes were not related.

The park said it waited to release the information until pathology tests confirmed that the animals died due to lightning. While there are multiple shelters available on the safari property for severe storm emergencies, the park said there is no way to force animals to use them. It is unclear whether the giraffes were killed by the same lightning bolt or separate strikes. The park now has 18 remaining giraffes in their care, and park spokeswoman Haley Passeser told NBC they are “looking at anything we can” to improve future safety for the animals.