Gorillas at the San Diego Zoo Safari Park tested positive for the novel coronavirus Monday, marking the first known case of the virus infecting any of the great apes — a group that includes gorillas, bonobos, chimps and orangutans.

Lisa Peterson, executive director of the Safari Park, said that more than one gorilla has tested positive but would not provide an exact number. During a Monday COVID-19 press briefing, California Gov. Gavin Newsom said that two gorillas have tested positive for the virus and that a third is showing COVID-19 symptoms.