Cops seize fireworks, make arrest after explosion By Amy Hollyfield WALNUT CREEK, California (KGO) — Walnut Creek police arrested 32-year-old Shayne Guerrero in connection with a loud explosion that happened Monday night and say they confiscated about $2,500 worth of fireworks from his home. The boom happened in between two buildings on the corner of Mt. Pisgah Road and Mt. Diablo Boulevard, across from Safeway and a block away from Nordstrom in Walnut Creek’s Broadway Plaza. Residents say they heard it, but did not know what it was. “It just sounded like this huge boom. I thought maybe construction fell over or maybe a car crash,” Nadine Hugg said Tuesday morning.