The FBI arrested a man in Arizona last week over online comments that allegedly incited what authorities described as a “religiously motivated terrorist attack” in Australia in which six people died, officials said Wednesday. Two police officers and a bystander were shot dead in an ambush when police went to a remote rural property in the state of Queensland on Dec. 12, 2022, authorities say. Gareth Train, brother Nathaniel Train, and Nathaniel’s wife, Stacey Train—who carried out the attack—were all killed by police. Now an unnamed 58-year-old man in Arizona has been detained on a U.S. charge for allegedly inciting the violence. “We know that the offenders executed a religiously motivated terrorist attack in Queensland,” Queensland Police Assistant Commissioner Cheryl Scanlon said, referring to the Trains. “They were motivated by a Christian extremist ideology.” Scanlon said the American had “sent messages containing Christian end-of-days ideology to Gareth and then later to Stacey,” though the FBI is still investigating the U.S. man’s alleged motive.