NEW YORK (AP) _ In an attempt to deter increasingly crafty shoplifters, a growing number of clothing stores are turning to a sort of doomsday device - a tag that, if tampered with, squirts the garment with an indelible dye.

The theory: Sometimes you have to ruin a dress to save it.

''If thieves know they can't sell it and they can't wear it, then they won't steal it,'' says Don Barnett, whose company makes ColorTag, one of two such products on the market.

The other is called INKTAG, and here's how it works.

You, the shoplifter, are strolling through a department store when you see an Anne Klein cream linen suit for $515 that you must have.

You notice a white plastic disc about two inches in diameter clamped on the skirt like a sandwich. It bears this ''WARNING: Forcing tag open causes breakage. Permanent ink sprays out. Injury can occur from broken glass, metal and ink.''

Since grenades are not customarily attached to dresses, you disregard the warning. Anyway, you figure, you can always remove the disc in the safety of your own home. So you take it into the dressing room, stuff it into your purse, and head for the exit.

You step out of the store, exultant. But when you get the dress home and try to pry the disc off with a screwdriver, your hands are suddenly squirted with blue, red and yellow ink that also stains the dress.

The stain wears off your hands in a few days, but repeated trips to the dry cleaner fail to eradicate the dress spot. You can't wear it anywhere, except to Halloween parties and the hipper downtown clubs.

Three vials inside the disc-tag were rigged to break when it did, releasing three teaspoons of ''a biological stain that interacts with the cells of natural fibers so it can't be washed out,'' according to Robert DiLonardo of Security Tag Systems in St. Petersburg, Fla., which makes INKTAG.

If the garment had been purchased, the tag would have been cleanly removed by a sales clerk with a small device bolted down next to the cash register.

DiLonardo said his company has sold several hundred thousand tags to 40 stores since production began last fall; ColorTag says its product, on sale for two years, now is used in hundreds of stores.

Michael Myers, vice president of security for the Casual Corner chain of women's clothing stores, says ColorTag has reduced losses by about 60 percent at the 40 stores where they have been tried. He described the reduction as ''incredible,'' and said the company plans to order more.

A quarter century ago, stores began tagging merchandise with magnetic strips and installing detectors at the door. But store security officials say professional shoplifters - who account for about 85 percent of all shoplifts - have learned how to remove the tags in the store and to shield them from the detector on the way out.

Meanwhile, shoplifting is soaring. Annual estimated losses exceed $25 billion, and one study found that shoplifters escape with the goods 97 percent of the time.

The ink tag concept originated in Sweden, and has been used in Europe for six years. Store security consultant Peter Berlin says that since such tags are more expensive than magnetic ones - INKTAGs cost about $2.75 each - they may be better suited for smaller clothing stores.

But Berlin says the tags appear to be effective. Despite the label warning, there is no explosion when the vials break, and little chance of accidents. ''It really has to be abused before it breaks,'' said DiLonardo.

Sometimes, however, clerks forget to remove the tags from purchased items. DiLonardo said one woman brought her wedding dress home and found the tag still attached; despite the warning, her fiance insisted he could get it off. He did - and she had to walk down the aisle in another dress.