Frontier crew members discovered two threatening notes on a flight headed from Seattle-Tacoma International Airport to Denver, according to the airline.

Around 4 p.m., the accused man entered Barnes and Noble at Deerbrook Mall and yelled that he had a bomb before running into the mall, Humble Police Chief Dan Zientek told reporters. In response and as a precaution, Texas Department of Public Safety officers helped clear the mall, a spokesperson for the Texas DPS confirmed.