When firefighters arrived, they discovered smoke and the sprinkler system activated inside.
FRESNO, Calif. (KFSN) -- Fresno firefighters are investigating what caused heavy smoke to plume inside a southwest Fresno warehouse on Wednesday morning.
Fire crews were called to reports of a smoke alarm going off inside the building on Fortune Avenue and Northpoint Drive just before 3 a.m.
When firefighters arrived, they discovered smoke and the sprinkler system activated inside.
Officials say the warehouse houses two businesses, including Universal Meditech, which manufactures pregnancy tests and IVF products.
A hazmat team was called to investigate potentially dangerous materials from that lab that may have been damaged. Investigators have been on the scene for a couple of hours.
No one was inside the building where the smoke started, but people in an adjacent business were evacuated by first responders.
Officials are investigating what combusted to cause the smoke.
The sprinklers caused a lot of water to spread to the adjoining business. Crews are now assessing the damage caused by the water and smoke.