HOUSTON -

Hot spots continued to pop up Friday, the day after a massive three-alarm fire broke out at an east Houston warehouse.

The fire started at Supply Pro Inc. in the 2100 block of Hahlo near Old Clinton Road about 2:20 p.m. Thursday. The blaze was contained to one warehouse, firefighters said.

Vivid orange flames shot out of the building, and thick, black smoke could be seen for miles.

Hahlo fire 47

"The fire started in the back and we were all on 911," said Bennie Murray, who has worked at Supply Pro Inc. for 10 years.

She said the building started filling with smoke and people began running.

Those within a five mile radius were asked to shelter-in-place. The shelter-in-place area was later narrowed to include areas between Kelly and Buffalo Bayou and Jensen to Lathrob. A reverse 911 system was used to alert citizens in the area. The shelter-in-place was lifted at 7:30 p.m.

Firefighters carefully monitored the air and water in the area. They have determined that the air is safe to breathe. The Texas Commission on Environmental Quality is also testing the air. Officials planned to run tests all weekend.

"It smells like rags burning, but worse," said Magdalena Ramos, who lives a few blocks away. "We pretty much stayed in the house. When we came back from the grocery store, we stayed inside and didn't go back out."

Henderson Elementary School was under a shelter-in-place, too, because students were on campus for summer school.

Approximately 45 fire department units responded to the scene, including the Hazardous Materials Unit.

Supply Pro Inc. makes spill containment boom and absorbent pads. The major product of concern on hand were propylene pellets. 

One firefighter was taken to a hospital after suffering heat exhaustion. He has been released from the hospital.

The cause of the fire is under investigation.

Officials said it could take weeks to clean up the warehouse.

RAW Video: 3-alarm fire in east Houston