Hazmat crew, firefighters respond to unknown fluid found under I-295 overpass in Mass.

ATTLEBORO, Mass. — A regional hazardous materials team and firefighters responded to an area near the Interstate 295 overpass on Thursday morning after two containers with an unknown dark liquid were found on the sidewalk.

The substance was later identified as mineral oil consistent with hydraulic fluid, fire officials said in a statement.

At about 10 a.m. Thursday, firefighters responded to Clifton Street under the I-295 overpass for a report of containers found on the sidewalk.

When firefighters arrived, they found two five-gallon containers holding an unknown dark substance, fire official said.

Crews also observed a foam-like material coming from the containers, indicating a possible chemical reaction.

As a precaution, a 300-foot section of Clifton Street was closed to traffic while first responders evaluated the scene.

Attleboro Fire requested a Tier 1 hazardous materials response.

A Massachusetts Department of Fire Services Hazmat Team arrived on scene at approximately 10:45 a.m.

Hazardous materials technicians obtained samples from the containers and tested them to determine the substance.

Initial testing confirmed there was no immediate threat to the public, fire officials said. Further analysis determined the fluid to be mineral oil, consistent with hydraulic fluid.

“When these types of emergencies are reported, there is no immediate way to determine what chemical may be present or how it might react,” Attleboro Fire District Chief Michael Maitland said in a statement.

“Containers holding unknown substances can pose significant health and fire hazards depending on their contents,” Maitland said. “We take these calls seriously to ensure the safety of the public and first responders.”

Once investigators found the substance was not hazardous, the Attleboro Health Department coodinated proper disposal of the material.

No injuries were reported.

Crews remained on scene until approximately 11:45 a.m.

“The Attleboro Fire Department reminds residents to dispose of chemicals and hazardous materials properly,” fire officials said. “Communities across Massachusetts hold household hazardous waste collection days throughout the year to allow residents to safely dispose of these materials.”

This is a developing story. Check back for updates as more information becomes available.

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