The fire quickly struck a 2nd and then a 3rd alarm due to the buildings close proximity of others structures near the fire.
According to the Republican Herald, the building was in the process of being tore down.
No other information is available at this time.
Republican Herald:
http://republicanherald.com/fire-destroys-vacant-building-in-pine-grove-1.1696476
WNEP:
http://wnep.com/2014/06/02/flames-rip-pine-grove-house/