HIALEAH GARDENS  (CBS4) – A possible grill explosion sent four people to the hospital.  Miami-Dade Fire responded to the call of a barbecue grill with a propane tank attached burning.

The explosion happened behind a home at 9885 Northwest 135th Street in Hialeah Gardens.

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Witnesses said about 20 people were in the backyard for a Fourth of July party.

Several people were injured.

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Out of the four people transported, three of them were considered trauma alert patients.

A family member told CBS4 “it was pretty bad.”

Air rescue responded to the call.

The victims were transported to Jackson Memorial Hospital.

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The conditions of the patients has not been released.