Louise Hart was standing in her store in Fairfax County's Thieves Market yesterday when she heard a low diesel rumble on the other side of the wall, then the unmistakable sound of a bulldozer trying to break through cinder block.

Hart, 68, who owns Hart's Antiques, and fellow owners of shops that sell antiques and second-hand goods from rugs to glassware, have known for some time that Thieves Market was to be demolished to make way for a beauty salon, a drugstore and other firms. But Hart said she didn't expect to hear the bulldozer until she had had a chance to pack the last of her inventory.

Leonard Romano, owner of Nardi Construction Inc., which is doing the work for the new property owner, Outlet World of Alexandria, said he was aware of the remaining tenants, but had written permission from Thieves Market owner Kap Cohen to begin demolition yesterday.

"We're right on schedule," said Romano.

As a result of the sale of the property, after 22 years in the building at 7704 Richmond Hwy. (Rte. 1), Thieves Market will move down the road, to 8101 Richmond Hwy. Cohen has operated a smaller branch of the antique market for five years and hopes to have the relocated shops open by the fall.

Hart was one of three remaining Thieves Market tenants who complained yesterday that they had paid rent through the end of July, and didn't expect to see heavy construction equipment until then.

Although the bulldozer never entered her store yesterday, and was eventually turned off altogether, it left a cloud of exhaust so thick inside the building that Hart had to step outside every few minutes for fresh air before continuing to pack. A friend of Hart's, 74-year-old Jerry Cabiness, was so sickened by the fumes that she was taken to Mount Vernon Hospital, where she was treated and released. Late yesterday, Cabiness was back at Thieves Market, but sitting in a doorway, where she could catch the breeze.

Cohen acknowledged the bulldozer had begun demolition before the end of the month, but called Hart a last-minute mover who has had 18 months to pack.

"She's just upset and frustrated because she's been there for 20 years," he said. "It's not an easy thing to do, and we feel badly for everyone involved, but we have to move."

He said the new Thieves Market will be operated much the same as the old, with 18 auctions a year and as many as 30 private dealers selling under the same roof.

As of yesterday, not much remained of the old Thieves Market, except piles of newspapers, rugs, china, pictures and other bric-a-brac at the Hart store, and two neighboring stores, including one owned by Ken Forster, 46.

"I thought we had until July 31," said Forster, struggling to pack his remaining $10,000 worth of glassware and jewelry.

Hart agreed. She said she was so desperate to get away from the diesel fumes and the bulldozers that she had put out an emergency plea to friends to help her move. Several showed up, including her ex-husband.

"I've been here for almost 20 years, and then to have an exit like this is very frustrating," she said.