EPA monitoring air quality after massive fire at old chemical building in Reading, Pa.

READING, Pennsylvania (WPVI) -- The EPA is monitoring the air quality in Reading, Pennsylvania, for signs of problems after a massive fire at an old chemical building in Berks County last week.

The fire broke out in the old Lincoln Chemical Company at 9th and Laurel streets. Action News reported that flames broke out twice during the same week.

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According to the fire marshal, the warehouse is no longer operational but still contained flammable items.

Heavy flames were showing from the third floor when crews arrived on the scene last week.

Chopper 6 was overhead as firefighters worked to get the flames under control.

There were abandoned chemical storage containers throughout the building so the EPA was immediately called in to assist.

There was a brief shelter-in-place order for neighbors during the second fire, which was later lifted.

No injuries have been reported.

The cause of the fire is still under investigation.

Initial air monitoring results have shown safe levels, however, the EPA said it will continue to monitor the area for several weeks.