Mount Vernon residents were told to shut their windows Friday night after a nearby chemical warehouse burst into flames.

The four-alarm fire at the KEM Chemical Corporation plant broke out around 7:30 p.m. KEM is a specialty industrial plant and laboratory supply distributor. The plant contains sulfuric acetones, creating purplish chemical flames that are difficult to fight.

The area around the plant was completely evacuated and roads were closed near South Fulton Avenue. Authorities say the fire spread to nearby businesses.

Mutual Aid from New Rochelle and Pelham, as well as the Westchester County Hazmat squad were on the scene. Con Ed was also there because they had to shut off gas to the building and power to the block.

Fire officials got the fire under control around 10 p.m. There has been no word yet on what sparked the blaze and no injuries have been reported.

The Red Cross assisted as well.