A mysterious black blob attacked downtown Los Angeles on Monday with a tar-like goo that oozed from manholes, buckled a street and unmoored a Raymond Chandler-era brick building, firefighters said. About 200 residents were forced to flee as a hazardous materials team and dozens of firefighters worked throughout the day to identify what was first deemed "a black tarry substance" and later morphed into a "watery mud." While outside temperatures struggled to break 60, sidewalks in the vicinity steamed at 103 degrees, Los Angeles Fire Department spokesman Ron Myers said. "It's worrisome in the fact that it will keep the...