Four people were taken to local hospitals by Oakland Fire Department after an unknown substance began giving off a strange odor at Oakland International Airport Tuesday morning.

CLICK HERE TO SIGN UP FOR OUR LIFESTYLE NEWSLETTER

An item inside a small cardboard box that was used at one of the airline ticketing counters for passengers to discard items banned from going through TSA, such as bottled water, aerosols and other contraband, reportedly began to emit a strange odor, a spokesperson for the airport told Fox News. The odor prompted the airport to call the fire department around 9:15 a.m.

There was no impact to airport operations and no injuries reported, though four people were taken to local hospitals for routine check-ups, the spokesperson said. (iStock)

CLICK HERE TO GET THE FOX NEWS APP

Hazmat crew responded to the airport, NBC Bay Area reported.

There was no impact to airport operations and no injuries reported, though four people were taken to local hospitals for routine check-ups, the spokesperson said.

FOLLOW US ON FACEBOOK FOR MORE FOX LIFESTYLE NEWS

The fire department is still investigating the cause of the odor.