It says on the article that he threatened to do self harm on twitter last night. Then when he went outside to smoke a cigarette in the morning, a police officer confronted him at his apartment for "welfare check". He had been carrying a 6-shot revolver outside while smoking a cigarette. The police told him to drop the gun and he ran into the woods. Then he called the local news station WRAL to do an interview with the local news while being chased by police. He was arrested like 3 hours ago.
(cw article has references to self harm)