Police Beat: The judge in the trial of a Baltimore police officer accused in the death of Freddie Gray declared a mistrial yesterday after the jury said it was unable to reach a unanimous verdict. Off. William Porter, 26, was charged …

Flight: A fire believed to have been set yesterday by an employee at a Chicago air traffic control center created snarls all over the country and led to the cancellation of about 1,750 flights. Passengers were stranded. Authorities say the …