Before gunning down 12 people at a city building on Friday, a longtime public utilities engineer had emailed his resignation to superiors, giving two weeks' notice just hours before the tragedy unfolded. City Manager Dave Hansen said that the engineer had not faced any ongoing discipline problems. Police Chief Jim Cervera stressed that the gunman had not been fired nor was he in the process of being let go in the days leading up to the city's deadliest shooting, as had been reported earlier. The schools administration building and the courthouse are open, the rest of the Municipal Center will reopen Tuesday, except for Building 2, where the shooting happened.