Tokyo explosion: Blast rips through downtown building, injuring 4

An explosion tore through a building in downtown Tokyo on Monday, scattering debris across a busy intersection and sending smoke into the air. According to the public broadcaster NHK, the fire was soon contained and only four people suffered light injuries. The cause of the blast was not immediately clear but witnesses said that they saw flames through the windows of the shattered second floor of the building and smelled gas.