An emergency tornado warning was in effect early Sunday on the University of Oklahoma's Norman campus, officials said. The warning was posted at 1:22 a.m. on the school's official X account. The school issued additional warnings at 1:55 a.m and 2:02 a.m.

At least six people were injured as severe thunderstorms moved across parts of Oklahoma early Sunday, with tornadoes and flooding reported overnight, authorities said.