January 9, 2013 – CALIFORNIA– The loud explosion that jolted North Hollywood on Tuesday night remained a mystery the next morning, authorities said. An officer at the Los Angeles Police Department’s North Hollywood station said police searched the area for a half an hour Tuesday night but had no luck in determining what caused the sound. The officer said police received numerous calls about the noise. At about 9:30 p.m., numerous people began tweeting about a loud explosion. Some thought it had come from a North Hollywood Metro station; others reported hearing an explosion in Studio City. “Mysterious explosion a few minutes ago. What’s going on? #LA” tweeted @ThatVitalSpark. “Seriously, any leads what the hell this boom was in North Hollywood? Im shook up a bit” tweeted @RajRawal37. A Reddit user posed the question: “What just blew up in North Hollywood?” By 10:30 p.m., there were more…