On this day in conspiracies

Adolf Hitler, then an army informant, attends his first DAP meeting and soon joins the party. He is drawn into the group Harrer helped create, but there is no record that he ever attended a Thule Society meeting or became a member.

Mattoon police publicly attribute the wave to a combination of mass anxiety and mundane causes (spilled solvents, factory odors, imagination) rather than a real gasser. New reports fall off sharply within days.

Around 7:15 p.m., brothers Edward and Fred May and their friend Tommy Hyer, playing near the school in Flatwoods, West Virginia, see a bright object streak across the sky and appear to come down on the hilltop farm of G. Bailey Fisher.

Biko dies in a Pretoria cell, aged 30. Justice minister Jimmy Kruger initially suggests he died following a hunger strike and remarks that the death “leaves me cold,” a comment that draws international condemnation.

The internet edition of the Jerusalem Post runs a story headlined that hundreds of Israelis are missing, reporting that Israel's Foreign Ministry had received the names of about 4,000 Israelis believed to have been in the areas of the World Trade Center and the Pentagon at the time of the attacks. It is a list of people whose safety families wanted checked, not a claim that anyone stayed away.

Maussan presents two boxed bodies at a Mexican Congress hearing on unidentified anomalous phenomena and testifies under oath that they are “non-human beings that are not part of our terrestrial evolution.” Scientists worldwide reject the presentation.

Bomb threats begin arriving in Springfield. City Hall is evacuated; over the following days, schools, two hospitals, Wittenberg University, and Clark State College are locked down, evacuated, or moved to remote operations. Governor Mike DeWine sends state troopers and bomb-sniffing dogs to secure schools.