Rescue workers searched rubble that witnesses compared to a warzone early Thursday for survivors of a fertilizer plant explosion in a small Texas town that killed as many as 15 people and injured more than 160 others, according to news agencies. The blast left the factory a smoldering ruin and leveled buildings for blocks in every direction. The explosion in downtown West, about 80 miles (130 kilometers) south of Dallas, shook the ground with the strength of a small earthquake and could be heard dozens of miles away. It sent flames shooting into the night sky and rained burning embers, shrapnel and debris down on shocked and frightened residents.