Before her arrest, Morgan Roof reportedly posted a message on Snapchat referencing Wednesday's national school walkout against gun violence.
The Oscar was stolen only momentarily before it was returned to McDormand, who allegedly told security to let the suspect go.
California authorities say Heather Locklear has been arrested for investigation of domestic violence and fighting with sheriff's deputies.
Benito Gutierrez, 69, and Carol Gutierrez, 64, were arrested after their adopted children were discovered living without access to food, water, lights, or a bathroom.
Israeli police have named the two close associates of Prime Minister Benjamin Netanyahu arrested for their suspected role in a wide-ranging corruption probe.