Jim Mahoney / The Dallas Morning News

Martin Hills and his dog Blackie watch the series of explosions from the Trinity River Levee.

DALLAS — People who were evacuated around the site of the explosion at the Southwest Industrial Gases facility on Industrial Blvd. may have to wait until Wednesday evening before they can return to the area.

Late Wednesday afternoon, Dallas Fire-Rescue said they will err on the side of caution as long as the fire is burning and firefighters are on the scene.

Officials said they don't have a precise number of homes and businesses that were evacuated; many residences in the danger zone were unoccupied because their owners had already gone to work.

Many of the stores in the area had not yet opened for business.

Along Industrial Blvd. and for several blocks from the explosion, ash-like debris will have to be cleaned up.

In some cases, gas canisters were flung up to a half a mile by the heat, but no one nearby was hit.

Some people watched the fire from the balconies of their apartments, just outside the evacuation zone, as massive plumes of smoke rose from the blast site.

The owner of one nearby business said if one of the gas cylinder has struck his office, it would have ripped through the building like it was paper.

Delivery driver Kevin Burks circled around West Dallas and the barricades for several hours, watching the flames and trying to get his produce to his customers.

"When the explosion first went off, I was getting a call," he said. "I heard the explosion, people were running and hollering, and they said, 'There's a big fire down there!' and before I knew it, they cut the whole interstate off. I had to wait and come around on Beckley here."

Others we talked to had similiar stories of long delays and a tough time getting to their destinations.

At 5 p.m., Dallas Fire Rescue officials said it could be several more hours before they open the streets and let people back in

E-mail dronan@wfaa.com Live in Dallas, Dan Ronan, channel 8 News.,