Firefighters have contained a smoky warehouse fire that burned more than four hours in Northwest Miami-Dade.

The fire started just after 7 Friday morning at the United Pillow company plant in a warehouse in the 5300 block of Northwest 35th court.

“You work like an animal and then this happens,” said company owner Mike Rodriguez.

Rodriguez said he came to work just after 7 a.m., turned on the lights and air conditioning and then left for a few minutes.

He came back to see flames shooting from his business.

“I have no clue what could have started it because there was nobody in there,” Rodriguez told CBS 4 News.

Because there were mountains of fabric and boxes within the business, the fire burned stubbornly.

More than 100 Miami-Dade and Hialeah firefighters were called to the burning warehouse.

“We are fighting it defensively in the air,” said Al Cruz of the Miami Dade Fire Department.

Many of the pillow company workers showed up with tears in their eyes. They are out of work for the moment. But Rodriguez said he will see what he can do to get them back on the job.

Rodriguez said he had already leased space in another warehouse nearby where he was planning to expand the business.

“They say what doesn’t kill you makes you stronger. We’ll figure something out.”

There were no injuries reported. The cause of the fire has yet to be determined.