http://seattlepi.nwsource.com/local/200175_seatac18.html Sea-Tac International Airport concourses were evacuated last night after an X-ray machine at the central checkpoint was suspected of malfunctioning, said Jennifer Peppin, a Transportation Security Administration spokeswoman. About 10 to 15 carry-on bags were allowed to pass through the suspect machine before security workers discovered the problem. Some 3,000 to 5,000 passengers had to vacate all of the airport concourses and go through security screening again around 9 p.m., Peppin said. Outbound flights were held or canceled, while incoming flights were being held on runways until the terminals could be cleared. Peppin estimated that it would take two to three hours to re-screen passengers. She suggested that people with flights this morning call their airlines before going to the airport.