GREAT FALLS, S.C. (AP) - A fire at an old cotton mill in Great Falls is keeping about 500 residents out of their homes.

The blaze at the former J.P. Stevens Number 3 mill started Tuesday morning and firefighters decided to let it burn itself out.

Great Falls Fire Chief John Jones says residents of four streets around the mill were evacuated because of the thick black smoke. That's about one-fourth of the town's population.

"I need to change my clothes," said Great Falls resident John Dye. "I've had this (t-shirt) on ever since yesterday and I can't get my deodorant and all that stuff; so it's rough."

Chester County Emergency Management Director Eddie Murphy says the evacuation could last up to a week.

Governor Mark Sanford visited the site Thursday and declared a state of emergency. That allows local governments to recover the cost of fighting the fire and protecting evacuated areas.

The cause of the blaze has not been determined.