Fire crews including multiple tankers were called to the Lapp Carriage Shop at 372 King St., in Myerstown around 7 a.m., according to Emergency Dispatch Services.
Pennsylvania State Police said only that one male was hospitalized with unknown injuries.
The incident was marked under control around 8 a.m.
There is no word on the extent of any damage. One person suffered burns, according the dispatch.
Abc27 reported that one girl died in an ambulance in route to the Lehigh Valley Burn Center, but Daily Voice has not been able to confirm this information.
The fire and explosion are under investigation by Pennsylvania state police.
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