OREGON - 3/28/10 - Authorities still don't know the cause of a Southeast Portland boom. It was the second mysterious explosion-like sound to hit the area in two weeks.
Portland authorities have no idea what caused the Sunday night boom that shook a number of residents' homes in Southeast Portland about 8:05 p.m. Many calls came in from the Sellwood neighborhood, but residents from Happy Valley to the Hillsdale area also reported hearing the ruckus. Portland Fire and Rescue sent several crews out, but "nobody could find anything." Portland Fire contacted the airport, but no causes were found there. Police were similarly stumped. There were no reports to confirm that a sonic boom occurred, which some Portland authorities guessed to be the cause. Residents reported a similar incident March 15, and no authorities ended up pinpointing the cause. Some pointed to fireworks as an explanation, but it was never confirmed. The latest one was much louder, and it was "very sudden, very quick." The mystery had the Portland area Twitterverse abuzz, as tweet after tweet referenced the "pdxboom."