URBANA, Ohio -- Fire crews responded to a chemical spill at 229 Elbert Street in Urbana on Wednesday night.

Police said the incident happened around 5 p.m. Officers blocked off the area and called the Environmental Protection Agency in to identify the substance.

Officials said about 10 days ago a 15-year-old boy found a baby jar full of mercury and opened it, spilling the chemical on his hands. They said the teen then walked through the house, spreading the mercury around.

EPA officials said the teen then spilled the mercury on the front porch. They said four people who lived in the house suffered exposure to the chemical.

Investigators said the house has been condemned. They said the U.S. EPA has been called in the clean up the substance.

EPA officials are calling the incident an extensive spill.