At least three people were killed in Thursday afternoon's huge gas explosion in Jankow Przygodzki, west Poland, according to Polish Media report. The blast, caused by a leak in a nearby gas line, caused three workers dead. They were employed on the construction of a new thread of the gas line. Thirteen people, including children were injured and have been sent to the hospital. The blast set fire to 10 houses. Till local time 19:00 (1800 GMT) on Thursday, four of the injured people went back home from the hospital with minor injuries. And the fire was under control.