DAISETTA, Texas —  The giant Texas sinkhole that formed last week is now a lake big enough to become the home of an alligator.

Area residents believe the reptile was washed into the 600-foot-diameter crater by water from surrounding swamps.

Ground water is seeping into the hole, and its exposed walls are about 30 feet high, the Houston Chronicle reported in its online edition on Friday.

Sightings of an alligator in the sinkhole were confirmed Friday when a Texas Railroad Commission worker snapped photographs.

Danny Diaz, a Texas Parks and Wildlife game warden, said a patch of crude oil floating on the east side of the crater might irritate the alligator's skin, but the reptile is using the water on the other side.

"It's not really safe for anyone to climb down into that hole now to get anything out," said Diaz, pointing to stress cracks in the ground that encircle the hole. "The sinkhole could start growing again, especially if we get a saturating rain."

The commission is still looking into what may have caused the collapse and if other underground voids might cave-in later.

The sinkhole in the small southeast Texas town of Daisetta began as a 20-foot hole in the ground but rapidly grew to 900 feet across at its widest point and 260 feet deep.

It has swallowed up oil tanks and barrels, tires, telephone poles and several vehicles in Daisetta, a town of around 1,000 residents located about 60 miles northeast of Houston.

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