Chicora, PA – Authorities are investigating an explosion that leveled a Butler County house. No one was hurt in the blast.

A woman had just entered the house with her 10-month-old daughter on Thursday when she heard what she described as a loud explosion. The two escaped unharmed and the house was destroyed.

The woman and her husband and daughter moved into the house about six weeks ago. They are now staying with relatives.

The cause of the explosion was not immediately known, but a propane tank at the house had been refilled earlier in the day.

About 50 firefighters from six fire departments arrived at the scene after the blast.