ARAPAHOE COUNTY, Colo. Three people were taken to the hospital as a precaution Tuesday after an unknown powder "exploded" inside a home in unincorporated Arapahoe County. The Arapahoe County Sheriff's Office and South Metro Fire Rescue were dispatched to a hazardous material investigation in the 1300 block of S. Willow Street Tuesday evening. The sheriff's office said a family found a small container on their front porch around 6:30 p.m. and brought it inside. When they opened it, a "white powdery substance exploded," according to ACSO. Three people were exposed to the substance and were taken to the hospital as a precaution. The sheriff's office said none of them appeared to have a serious reaction to the powder. SMFR said the powder was tested but the tests came back "inconclusive." HAZMAT teams and the ACSO Bomb Unit are working to determine what the substance is. There is no threat to the community, according to SMFR. Residents and neighbors will be allowed back into their homes once authorities process the scene.