NISKAYUNA, N.Y. (NEWS10) — Crews responded to a HAZMAT situation at an office building on Balltown Road in Niskayuna Monday.

There were initial reports of an unknown odor, but HAZMAT crews are unsure of what caused several people to get sick.

Officials estimate as many as 20 people at the Capital District Disabled and Special Needs and Services building came down with symptoms of vomiting, scratchy throat, coughing and itchy eyes.

Most left before crews could evaluate them, and without a cause, it could be business as usual on Tuesday.

Stanford Heights Fire Chief John Courter said all tests came back negative.

“We turned it back over to their business staff,” he said. “They’ve made all their notifications to their state heads that they have to, and like I said, as far as the fire department is concerned, we’ve done everything that we can on our end. Everything checks out okay.”

Although it is unknown what happened, area hospitals have been notified.