BOSTON (CBS) – Several buildings were evacuated in Boston’s Fenway neighborhood after unknown chemicals were discovered in the basement of a business Tuesday night.

Hazmat crews, the FBI Joint Terrorism Task Force, police and fire all responded to the Fenway Market on Kilmarnock Street after an anonymous tip came into Inspectional Services.

READ MORE: LOOK: Killer whale spotted by fisherman off Nantucket

Along with the chemicals, heating elements and other types of machinery were found in the basement, leading police to believe that it was being used as a lab.

“We’re just trying to figure out what particularly is in that basement,” Boston Police Commissioner William Evans said. “Obviously it has nothing to do with the market’s purposes.”

Police say initial testing on the chemicals revealed that they are not as alarming as they previously thought. Commissioner Evans says they are not drug related, although he cannot say what they are.

“A large amount of chemicals, acids and some other substances,” Evans said.

READ MORE: Boston makes top 20 in ranking of America's 'best places to live'

Initial testing also suggests they are not explosives.

Residents were eventually allowed to return to their buildings, with the exception of those who live right next to the market. Those who return home are still being asked to stay away from their windows.

Mass. Department of Environmental Protection at the scene of a hazmat incident in Boston (Photo from Julie Loncich/WBZ)

Mass. Department of Environmental Protection at the scene of a hazmat incident in Boston (Photo from Julie Loncich/WBZ)

A Boston Fire official says the chemicals are in containers and were found during an inspection of the business after an anonymous complaint was made. There was no leak or spill.

MBTA buses are being used to shelter people who have been evacuated in the area.

MORE NEWS: Weekend heat likely to break records with low-mid 90s in the forecast

Boston Police are urging the public to avoid the area.