Police officers and EMS providers are among the seven people injured following an explosion at a nail salon in Windsor Mill, Maryland, Monday night, authorities said.

       Four police officers, two EMS providers and one civilian were hospitalized after the "minor explosion" at a strip mall, the Baltimore County Fire Department said.

       The explosion took place at the Libra Nails & Spa on the 1700 block of N. Rolling Road. The fire department responded to a call for a commercial building fire possibly involving hazardous materials, it said.

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       Investigators were called to the scene for possible criminal activity, and the Bureau of Alcohol, Tobacco, Firearms and Explosives is assisting the investigation, ABC News Baltimore affiliate WMAR reported.

       The fire is under control, authorities said.

       ABC News' Chad Murray contributed to this report.