The police are completely irresponsible when they make these lone wolf statements. Yes they may be correct he was the lone shooter, but very possible someone was aiding and abetting. You’d need a forensic IT team to search the guys phone, computer, email and social media accounts, as well as a boots on the ground police investigation of banking transactions, recent travel, interview of witnesses, before you could make such a definitive statement.
minimum support group of 3 - 5