PITTSBURG (CBS SF) — Residents in the area of Central Avenue and MacArthur Avenue near Pittsburg High School were asked to shelter-in-place as a bomb squad detonated an explosive device Sunday night.

The explosive was found inside a vacant home on Somers Street. No one was injured.

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Police say the explosive device was several flares wrapped together with rifle rounds.

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Investigators are attempting to find the tenants who last lived in the home as an investigation into the case continues.

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