DAISETTA, Texas -- A monster sinkhole the size of several football fields continues to grow and is causing serious concern in the Liberty County town of Daisetta.

What started as some big cracks in the road Wednesday morning grew to a huge hole by the afternoon.

From Air 11, the long crater on Highway 770 near FM 834 appeared to be about as wide as two football fields and 10 stories deep. It is partially filled with a black liquid believed to be oil or oilfield sludge.

And it was hungry. The hole gobbled up an 18-wheeler, a drilling platform and other oil field equipment.

As Air 11 flew back over the scene Wednesday afternoon, a tractor fell into the hole as the ground crumbled beneath it.

Crews worked feverishly to pump hundreds of barrels of oil out of storage tanks before they fell in.

AIR 11

By Wednesday afternoon, the sinkhole had grown by leaps and bounds.

"Right now we're not concerned about any kind of explosion or any kind of hazard," said Tom Branch with Liberty County Emergency Management. "We are monitoring some other things around the area to make sure everyone's OK."

11 News photo

Utility crews had to cut a power line because the poles were falling into the sinkhole.

"There is some more that's falling in," said Hugh Bishop with the Liberty County Sheriff's Department. "The road that drives out into the oil field, there's more cracks showing up in that so we're just trying to take every precaution and get people back 'cause we don't know exactly what's going to happen with it."

AIR 11

This tank rolled into the sinkhole when the ground beneath it collapsed.

Emergency crews from the Daisetta Fire Department were on the scene trying to figure out how to stop the sinkhole from growing.

Experts from the Texas Railroad Commission, the Environmental Protection Agency and the Texas Commission on Environmental Quality were also on the scene.

The Houston Fire Department sent its HazMat unit to help out.

Highway 770, Daisetta's main drag, had to be shut down because the sinkhole was within 50 yards of the roadway. School buses and other vehicles were diverted around the area.

Several smaller cracks appeared in the road surrounding the big one. From Air 11, you could see the cracks formed an almost a perfect circle.

Daisetta -- population 1,000 -- was once a booming oil town, and that past may be to blame for the sinkhole. Experts believe the ground collapsed because of an old salt dome where oil brine and natural gas are stored underground.

Liberty County is about an hour northeast of Houston.