Rescuers are scouring the wreckage of a Dallas apartment building for any additional victims after a massive explosion and fire killed at least three people, including a child. The blast occurred Thursday afternoon as firefighters were rushing to investigate a reported gas leak. The powerful explosion shook nearby homes and quickly engulfed the two-story complex in Dallas’s Oak Cliff neighborhood, south of downtown. A towering plume of black smoke was visible for miles after the explosion. In addition to the three fatalities, at least five people were injured and taken to hospitals, according to Dallas Fire -Rescue spokesperson Jason Evans. The exact number of residents in the destroyed complex remains unclear. By Friday morning, several blocks surrounding the explosion site remained sealed off by police cars and tape. Law enforcement officials and workers in bright yellow vests could be seen sifting through the rubble of what was once the apartment building.…